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The Trump administration announced on Monday that it will implement several changes to the Endangered Species Act—changes that will, according to conservation advocates, weaken legislation that has played a pivotal role in protecting the nation’s at-risk wildlife.
Signed by President Richard Nixon in 1973, the Endangered Species Act (ESA) currently protects 1,663 animal and plant species, 388 of which are considered threatened and 1,275 are endangered. The law has been credited with helping bring multiple species back from the brink of extinction, among them the bald eagle, the humpback whale, the California Condor and the American alligator. But as Reuters notes, “the law has long been a source of frustration for drillers, miners and other industries because new listings can put vast swathes of land off limits to development.”
Republicans have long pushed for an overhaul of the law. And the new rules, which are expected to go into effect next month, “appear very likely to clear the way for new mining, oil and gas drilling, and development in areas where protected species live,” according to Lisa Friedman of the New York Times.
One of the key changes pertains to threatened species, which are one classification below endangered species but used to automatically receive the same protections. Now, protections for threatened plants and animals will be made on a case-by-case basis, slowing down the process and likely reducing overall protections for species that are ultimately added to the list, as Brett Hartl, government affairs director for the Center for Biological Diversity, tells Nature’s Jonathan Lambert.
The new rules also impose limitations on how threats are assessed. Officials used to take into account factors that could harm species in the “foreseeable future,” but now lawmakers have more discretion in deciding what “foreseeable future” should mean. So they may choose to disregard climate factors—like rising sea levels and extreme heat—that will likely impact species several decades from now.
Additionally, the revisions curtail an important function of the ESA: protecting lands that at-risk species need to survive. One new stipulation requires regulators to assess lands that are currently occupied by threatened or endangered species before looking at unoccupied areas. But as Madeleine Gregory of Vice explains, many species are at risk precisely because they have been forced into a small fraction of their original habitat, and protecting more land around them can help species recover.
Yet another change to the ESA saw the removal of language stipulating that only scientific evidence should be considered when deciding whether a species should be protected, essentially allowing reviewers to take economic loss into consideration as well. Gary Frazer, the assistant director for endangered species with the United States Fish and Wildlife Service, stressed in a press conference that listing decisions will continue to be based on science. But allowing economic analyses to factor into the process, even just for “informational purposes,” is a “giant concession to industries that have long complained about having to make excessive accommodations because of the law,” the Los Angeles Times writes in an op-ed.
In a statement, U.S. Secretary of Commerce Wilbur Ross said that the new revisions “fit squarely within the President’s mandate of easing the regulatory burden on the American public, without sacrificing our species’ protection and recovery goals.” But critics maintain that regulations will in fact hamper conservation efforts at a time of biodiversity crisis. In May, the United Nations released an alarming report stating that one million species are at risk of extinction, due to factors like climate change, pollution, deforestation, overfishing and poaching. Advocates say that to ensure the long-term sustainability of the planet’s ecosystems, 30 percent of terrestrial and inland water areas and 30 percent of the world’s oceans will need to be effectively managed by 2030.
"Instead of looking for solutions to the global extinction crisis that threatens up to one million plant and animal species, this administration has decided to place arbitrary and unlawful restrictions on the very federal regulators that Congress has tasked with protecting them," David Hayes, executive director of the State Energy & Environmental Impact Center at NYU School of Law and a former interior deputy secretary under the Obama and Clinton administrations, tells the Ellen Knickmeyer of the Associated Press.
Conservationists and multiple state attorney generals have promised to sue the administration over the revisions, arguing that they are illegal because they are not rooted in scientific evidence, according to NPR’s Nathan Rott.
"This effort to gut protections for endangered and threatened species has the same two features of most Trump administration actions: it's a gift to industry, and it's illegal,” Drew Caputo, a vice president of litigation for the advocacy group Earthjustice tells the AP. “We'll see the Trump administration in court about it.”
"There is no subject attracting more attention at the present time among men of science throughout the world, than the newly discovered process of spectral analysis," announced Scientific American in July 1861. The reference was to Robert Bunsen and Gustav Kirchhoff, two German scientists who, having seen a correspondence between the bright colors of incandescent substances and the dark lines crossing the solar spectrum, realized that they had found a way to determine the chemical composition of the sun and other celestial bodies. Returning to the subject some weeks later, Scientific American announced the spectroscopic discovery of cesium, rubidium and thallium, substances hitherto unknown on earth, adding that, "We may reasonably anticipate many new discoveries, and a great development of chemistry from this peculiar mode of qualitative analysis."
Scientists weren't the only ones excited by the promise of spectroscopy. Indeed, a survey of popular literature shows that spectroscopy's potential captured the imagination of Americans of many walks of life. Godey's Lady's Book described spectroscopy as "one of the greatest marvels of modern science." The Baptist Quarterly claimed that the history, processes, achievements and possibilities of spectroscopy constitute "one of the marvels of the nineteenth century, and entitle it to the consideration of every thoughtful mind." Perhaps referring to current concerns over Darwinian evolution, this publication went to say that "the days are happily gone by—forever, let us hope—in which the wondrous disclosures of physical science are of less interest to the Christian community than they are to the secular public." James McCosh, the Presbyterian president of the College of New Jersey (now Princeton) saw in spectroscopy evidence of intelligent design in the universe.
Scientific American termed the spectroscope the "latest miracle of science." For Leroy Cooley, a professor of science at Vassar College, it was "an instrument the delicacy and accuracy of whose announcements are unsurpassed." A popular French book on optics that saw several American editions said that the spectroscope "may fairly rank, after the telescope and the microscope, as one of the most wonderful discoveries of modern optical science." With such outpourings of enthusiasm, it is not surprising that examples were soon to be seen in colleges across the country, as well as in the hands of a few wealthy individuals.
Deborah Warner is a Curator of the Physical Sciences Collection in the National Museum of American History.
Plenty of souls have searched for answers at the bottom of a glass of whisky. For Phoenix-based artist and photographer Ernie Button, that quest revealed some unexpected beauty, and set him out on a search for truth.
Over the last few years, Button has been capturing stunning images, like the ones seen above, of the dried patterns that whisky leaves at the bottom of a glass. Recently he teamed up with Howard Stone, an engineer at Princeton University, whose lab found that some basic fluid dynamics drive whisky’s unique pattern formation. They presented their findings today at a meeting of the American Physical Society (APS) in San Francisco, California.
Button’s fascination with whisky began when he married into his wife’s Scotch-drinking family. While doing the dishes at home, he noticed that lacy lines covered the bottom of a glass of single-malt scotch. Other glasses appeared to produce various patterns of dried sediment. “It’s a little like snowflakes, in that every time the Scotch dries, the glass yields different patterns and results,” says Button. He thought that trying to capture the patterns might make for an interesting photography project.
Creating the images required a bit of Macgyvering. On their own, the grayish sediment lines are a bit underwhelming compared to the amber liquid that creates them, so Button had to experiment with different glasses and lighting systems. Using flashlights and desk lamps, Button highlights the patterns with different hues. “It creates the illusion of landscape, terrestrial or extraterrestrial,” says Button. To him, many of the images appear celestial, perhaps something that a satellite camera might snap high above Earth. Other images could easily be frigid polar vistas or petri dishes of bacterial colonies.Glen Moray 110 (Ernie Button)
Button captured a lot of variety through his camera lens, and he began wondering if it had something to do with the age of the liquid. After some experimenting, though, he saw little difference in younger and older versions of the same type of whisky. With some Googling, he came across Stone’s lab, then at Harvard and now at Princeton. Stone and his colleagues happily answered questions over email, and the conversation got them thinking as well.
Stone initially suspected that something called the coffee ring effect might be at play: When coffee dries, particles are pulled to the edge of where the liquid makes contact with the cup, creating ring-like patterns as the water evaporates. Similarly, the differing evaporation tendencies of alcohol and water can create interesting patterns, like the "legs" on a wine glass. This is largely driven by the Marangoni effect, first described by 19th-century physicist Carlo Marangoni. Alcohol and water have different surface tensions—that’s the degree of attraction liquid molecules have to other surfaces (in this case a cup or a glass). Alcohol has a lower surface tension than water, and alcohol evaporation drives the surface tension up and pushes more liquid away from areas of high alcohol concentration.
In the case of whisky, the patterns were more uniform, with particles settling in the middle of a droplet of liquid. So was there something about whisky that created unique patterns compared to other types of liquors?
Not a whisky drinker himself, Stone ran to the store to buy a bottle or two, and his team began tinkering around in the lab. Under the microscope, they made videos of whisky drying and compared them to videos of a mixture of alcohol and water that mimics the proportions of whisky (about 40 percent ethanol, 60 percent water). The fake whisky followed Marangoni flow: Ethanol evaporated first, drawing the particles into a ring-shaped pattern. The higher the alcohol content, the smaller the ring. But whisky, as Button had observed, didn’t produce clean rings. “That says there’s something in your mixture that’s missing,” explains Stone.
Next they added a soap-like compound, which sticks to the surface of water, to their faux-whiskey. Lots of compounds can do that, so they thought whisky might contain something similar. But the patterns still weren’t quite right. Next they added a larger molecule (a polymer) that might help whisky stick to the surface of the glass. Finally, the mixture droplets were doing roughly the same thing as whisky droplets.
Based on this work, the lab team has a hypothesis: “Very small amounts of the additives that come from how whisky is made contribute to the kinds of patterns you actually see,” says Stone. Different additives or variations in the manufacturing process might possibly produce different patterns.
The research has some practical implications. Better understanding of these types of fluid flows could prove useful in a lot of industrial situations that involve liquids, particularly liquids that contain particles of sediment or other material, such as printing inks. In the meantime, Button hopes his images raise questions in the minds of viewers that may give them some interesting conversation starters at cocktail parties. “The science behind the imagery provides that extra added layer of thought and complexity,” he says.
For more images and information about Ernie Button’s work and upcoming exhibitions, check out his website.
What goes up must come down, right? That’s not necessarily true in space, where satellites swarm around the planet, locked in by speeds that help defeat the downward pull of gravity.
Although satellites do come down more often these days—mostly the result of a life of planned obsolescence—some have floated around for years, if not decades, without a pre-programmed fall-back-to-Earth date. And that’s cluttering the orbital space.
So what keeps them in orbit? Satellites—that is, artificial satellites, as opposed to natural satellites like the moon—are carried into space by rockets. The rocket must fly 100-to-200 kilometers above the earth to get outside the atmosphere. Once at a pre-determined orbit elevation, the rocket starts heading sideways at speeds of up to 18,000 miles per hour, says Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
The rocket switches off and drops its payload—the satellite—which is now in the same orbit, zooming along at those same speeds. The Earth is curving away while both the rocket and the satellite “fall” around the Earth. The satellite stays in that orbit as long as it keeps its speed to stay balanced by the headwinds.
At those heights, the atmosphere is just thin enough to prevent the satellite from burning up—as it will if it drops lower and encounters thicker air, which causes greater headwinds and thus greater friction.
Most satellites are dropped in a range of up to 2,000 km above the earth. The satellites in the very low end of that range typically only stay up for a few weeks to a few months. They run into that friction and will basically melt, says McDowell.
But at altitudes of 600 km—where the International Space Station orbits—satellites can stay up for decades. And that’s potentially a problem. They travel so fast—5 miles a second—that their “footprint” can be hundreds of miles long. “When you think of them as being that big, suddenly space doesn’t look as empty anymore,” McDowell says.
The first satellite was launched by the former U.S.S.R. in late 1957. The Sputnik-1 became an icon of modernity and prodded the U.S. into further accelerating its own space exploration plans. Just months after Sputnik, America launched Explorer-1. In the intervening decades, thousands of satellites have been carried up into space.
McDowell keeps close tabs on the action. By his reckoning, there are some 12,000 pieces of space debris and several thousand satellites in orbit, with a little over a thousand that are still active. However, the active count “is uncertain, as monitoring of radio transmissions from these satellites to their owners is not widely done—except perhaps by the National Security Agency—and sometimes the owners, especially military ones, don’t tell me when their satellites have been switched off,” says McDowell.
About a third of satellites are owned by various militaries, of which a third to a half are used for surveillance, he says. Another third are civilian-owned, and the final third are commercial. Russia, the U.S., China and Europe are the main players in the launch business, but many other countries have capabilities or are developing them. And dozens of countries have built their own satellites—launched by other nations or commercial space companies.
And the trend is to send up devices with long lifespans—10- to 20-years on average. On top of that, retired or dead satellites mostly stay in orbit, powered by solar panels.
Adding to the mix: the burgeoning “personal” satellite business. These micro satellites have largely been developed and used by universities, but at least one company is selling directly to the public and there are D.I.Y. sites, also.
The dissemination of satellite technology is driven in part by the same factors that have resulted in the spread of other formerly sophisticated technologies, like gene sequencing—more knowledge, faster computing, and less-expensive machinery. But also “there are more tickets to ride available”—more launch opportunities, says McDowell.
All of which makes for an ever-more-crowded orbital space.
There are lots of near-misses—with engineers playing the role of air traffic control from Earth, maneuvering the satellites out of harm’s way as needed. Satellite owners have been asked—by NASA, among other space agencies—to take steps to reduce the likelihood that today’s prized flying machine doesn’t become tomorrow’s floating bucket of junk. That’s being done by pushing low orbiters into the burnout zone or deliberately crashing large satellites into the South Pacific, McDowell says.
In the meantime, the Earth may be reaching its capacity for orbiting objects.
Just as humans have become more aware of the need for stewardship of the terrestrial environment, “we’re going to have to be serious about the ecology of near outer space,” says McDowell.
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Early yesterday morning, NASA launched a SpaceX Falcon Heavy rocket into orbit with a hodgepodge of science missions aboard. One of the most intriguing payloads was a clock, which will tick along for about a year as it circles the planet. But this is no ordinary clock: the Deep Space Atomic Clock is a technology that could make navigating deep space much easier in the future.
Kasandra Brabaw at Space.com reports that most probes sent into the cosmos are tracked from Earth via radio waves, which travel at light speed. A signal is sent from Earth and immediately bounced back to mission control, allowing the probe’s handlers to calculate its exact position based on how long it took the signal to reach them. That process relies on NASA’s Deep Space Network, an array of radio antennas that can only handle so much space traffic at any given moment.
If the probes had clocks stable and precise enough to allow them to chart their own course, however, they could do some of that navigation autonomously, reports Jonathan Amos at the BBC.
“Autonomous onboard navigation means that a spacecraft can perform its own navigation in real-time without waiting for directions to be sent from navigators back here on Earth,” deputy principal investigator Jill Seubert recently told reporters at a press conference. “Self-driving” spacecraft are also a key part of putting humans on Mars. “And with this capability, a human-crewed spacecraft can be delivered safely to a landing site with less uncertainty in their path.”
But even the nicest Rolex won’t cut it in space. Quartz crystals oscillate at a regular frequency when electrical current passes through them, which is why they are used to in clocks to keep track of time. They’re precise enough when it comes to getting up for work or catching a train, but they’re not nearly accurate enough on their own for navigating in deep space. They can lose a full millisecond over the course of six weeks, which would be disastrous for a space probe.
To get the billionth-of-a-second precision needed to fly through the cosmos requires an atomic clock, a gadget that trains its quartz crystal to the oscillations of certain atoms. The electrons around these atoms occupy distinct energy levels, or orbits, and it takes a precise jolt of electricity to cause them to jump to the next energy level. “The fact that the energy difference between these orbits is such a precise and stable value is really the key ingredient for atomic clocks,” Eric Burt, an atomic clock physicist at NASA’s Jet Propulsion Laboratory, says in a press release. “It's the reason atomic clocks can reach a performance level beyond mechanical clocks."
In an atomic clock, the frequency of the quartz oscillator is fine tuned to match the energy needed to pop electrons to a new energy level. When the quartz is vibrating at the right frequency, the electrons will jump to the next energy level. If they don’t, the clock knows the frequency is off and can correct itself, a process that occurs every few seconds.
Currently, most terrestrial atomic clocks are the size of a refrigerator. Enter the Deep Space Atomic Clock, which NASA engineers have been tinkering with for almost 20 years. The gadget, about the size of a toaster, uses charged mercury ions to keep its quartz oscillator true, and loses only about one nanosecond over four days. It would take about 10 million years for the clock to be off by one second, making it about 50 times more stable than the precise clocks used in GPS satellite navigation.
The clock is currently in low Earth orbit and will power on in four to seven weeks. After three to four weeks of operation, researchers will analyze its preliminary performance and will give a final verdict on how well it works in space after it zooms around the planet for about a year.
If the clock is stable enough, according to a NASA statement, it could begin appearing in spacecraft by the 2030’s. Whether this version survives or not, atomic clocks or a similar technology will be critical in future space missions to other worlds.
“The Deep Space Atomic Clock will have the ability to aid in navigation, not just locally but in other planets as well,” Burt says. “One way to think of it is as if we had GPS at other planets.”
Other experiments that went into orbit with the clock include the Green Propellant Infusion Mission ,which is testing a system that uses high-performance, non-toxic space fuel, and the Enhanced Tandem Beacon Experiment, which will explore bubbles in the electrically-charged layers of Earth’s atmosphere that can sometimes interfere with GPS signals.
Antarctica is the go-to spot to collect cosmic dust—the tiny grains of space rock that date back to our planet's infancy. These specks from space are challenging to find and previously thought impossible to separate from the chaos of urban debris.
But a new study, recently published in the journal Geology, suggests that cosmic dust may be found closer to home. Matthew Genge from Imperial College London and amateur Norwegian scientist Jon Larsen combed through 660 pounds of gunk collected from gutters in Oslo, Paris and Berlin, finding 500 particles of cosmic dust, according to a press release.
“We’ve known since the 1940s that cosmic dust falls continuously through our atmosphere, but until now we’ve thought that it could not be detected among the millions of terrestrial dust particles, except in the most dust-free environments such as the Antarctic or deep oceans,” Genge tells New Scientist. “The obvious advantage to this new approach is that it is much easier to source cosmic dust particles if they are in our backyards.”
JoAnna Wendel at Earth & Space Science News points out that there several educational websites that encourage people to collect debris from their gutters. They say that anything spherical or magnetic could be a micrometeorite. But researchers have poo pooed that idea and have long thought it was impossible to distinguish between space dust and industrial pollution.
But Larsen was not convinced, Wendel reports. For six years, he collected urban dust and debris from cities around the world, sifting through hundreds of pounds of dust and looking at 40,000 bits through the microscope. One thousand of those were convincing enough to put under a scanning electron microscope. In February 2015, he finally found one particle with the telltale marks of a micrometeorite. That’s when he approached Genge about his find.
“When Jon first came to me I was dubious,” Genge says in the press release. “Many people had reported finding cosmic dust in urban areas before, but when they were analyzed scientists found that these particles were all industrial in origin.”
But this urban space speck convinced him. So he helped Larsen refine his hunting techniques. Since then, Larsen has recovered 500 of the particles. They are slightly larger than average, measuring about 0.3 millimeters compared to the usual 0.01 millimeters, according to New Scientist. Analysis suggests that they likely melted while hurtling through earth’s atmosphere at 12 km per second, the fastest any dust particle has traveled on Earth.
These urban micrometeorites also suggest that the dust making it to Earth has changed over time, according to the press release. Dust captured in Antarctic ice is much more ancient, accumulating over the last million years. And unlike these minute particles, the urban cosmic dust contains feather-like crystals. The urban particles are, however, similar to dust that has fallen since Medieval times.
The difference in size is probably caused by slight changes in the orbits of Earth and Mars, Genge explains in the press release. This change affects the gravitational pull on the particles, causing them to come in faster and heat up more, which alters their size and shape. Those changes, he says, are important to understand if cosmic dust is used to reconstruct the geologic history of the solar system.
While the research is interesting and Larsen’s dedication is impressive, Susan Taylor, a research scientist at the U.S. Army Cold Regions Research Laboratory tells Wendel it's unlikely that she and other scientists will start scouring local gutters anytime soon. Finding 500 particles in 600 pounds of gunk is slow going, compared to the thousands of micrometeorites she can pull out of a single bore hole in Antarctica.
Yet, it's still fun to consider that there's more to the dust in the street than industrial pollution—you could be looking at some specks from space.
On November 26, 2018, NASA’s InSight lander began its perilous descent down to the surface of the Red Planet. Tracking the probe’s progression through the Martian atmosphere, personnel at mission control endured “seven minutes of terror”—a period of absolute helplessness, during which scientists could do nothing but wait with bated breath until their spacecraft confirmed it was safe.
The touchdown was “flawless,” NASA employees announced that day. And in the 16 months since, InSight has proved itself to be well worth the effort. The lander’s first big batch of data, described in a suite of studies published this week in Nature Geoscience and Nature Communications, has pulled back the curtain on many once-mysterious aspects of Mars, including its intriguing seismic activity and surprisingly strong magnetic field.
Shortly after settling near the Martian equator a year and a half ago, InSight got busy, deploying an array of instruments, including several ultra-sensitive seismometers and a burrowing heat probe.
In April 2019, InSight’s seismometer detected its first marsquake: a subtle rumble that hinted that, despite its decidedly non-Earth-like geology, Mars’ interior has its own terrestrial temper. “We’ve finally, for the first time, established that Mars is a seismically active planet,” InSight principal investigator and NASA planetary scientist Bruce Banerdt said during a teleconference on February 20.
Since that first find, the lander has detected more than 450 other tremors of varying severity, including several dozen belched up from the planet’s mantle, roughly equivalent to magnitude 3 or 4 quakes here on Earth, reports Ian Sample for the Guardian. On average, Mars seems to shake more than the moon, but still pales in comparison to helter-skelter Earth. Were they to happen on Earth, most marsquakes would barely be detectable, seismologist Philippe Lognonné tells Ben Guarino at the Washington Post.
Still mysterious, however, is the origin of these extraterrestrial trembles. While earthbound quakes arise when our planet’s tectonic plates grind up against one another, Mars lacks the same internal architecture, leaving researchers puzzled about the source of its quakes.
But two temblors that appear to have arisen from a Martian structure called Cerberus Fossae, a series of deep surface fissures that were recently geologically and volcanically active, have provided researchers with hints, InSight deputy principal investigator Suzanne Smrekar tells the Washington Post. Based on InSight’s data, researchers think pockets of magma may still be moving, cooling and contracting deep in the Red Planet’s innards, causing cracks, then quivers, at its brittle rocky surface, reports Maya Wei-Haas for National Geographic.
Also described in the new finds is a mysterious and persistent hum that pervades the Martian landscape. Though the slosh of Earth’s oceans produces a comparable sound, scientists have yet to suss out a plausible cause for the Red Planet’s curious tune. “It’s extremely puzzling,” Banerdt tells National Geographic.
Another surprise has come from data collected by InSight’s magnetometer, which has picked up on a local magnetic field about ten times stronger than researchers expected to see. Though Mars once had a magnetic north and south like Earth, its internal dynamo, or liquid metal interior, stopped churning billions of years ago, stripping the planet of its global magnetic field. (This change also purged the planet of much of its protective atmosphere, exposing its surface to a barrage of space weather and turning what was once a warm, wet world into a frigid, parched desert.)
But magnetic minerals still exist in Martian rocks, locked in like a time capsule of the planet’s long-gone magnetism. “They’re like little tape recorders,” InSight team member Catherine Johnson told the Washington Post. Combined with a series of pulsating electric currents found in Mars’ atmosphere, these blips of local magnetism may be the source of InSight’s unexpected detection.
“This measurement was our first little tiny taste—one single point—of how much stronger the magnetization might be,” Robert Lillis, a planetary space physicist at the University of California, Berkeley who wasn’t involved in the studies tells National Geographic.
InSight is still fervently collecting data, which NASA is releasing to the public at three-month intervals. Once cache of results, though, has so far been conspicuously absent: readings from the craft’s subterranean heat probe, nicknamed the “mole,” which has been unable to penetrate the cementlike soil that cakes InSight’s landing site. Over the next couple months, mission team members will try to leverage the robot’s arm to help the mole break ground, reports Mike Wall for Space.com.
For the most part, though, things on the Red Planet remain on track, team members report. As Banerdt tells Space.com, “I think we're well on our way to getting most, if not all, of the goals that we set for ourselves ten years ago when we started this mission.”
At 12:33 a.m. EST on January 1, 2019, more than four billion miles from Earth, a NASA spacecraft launched in January 2006 will fly within 2,200 miles of an ancient planetary body, orbiting more than 40 times the distance from the Earth to the sun and undisturbed for perhaps billions of years. The New Horizons flyby of 2014 MU69, aptly nicknamed Ultima Thule for a Latin phrase meaning beyond the known world, will not only be the most distant planetary encounter in human history, but the object will also be the most primitive world ever visited by spacecraft.
As the clock strikes midnight on the east coast of the United States, you can tune in to NASA TV to join the space agency at mission control in the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, as the world celebrates the arrival of New Horizons at Ultima Thule. Talks and presentations by members of the mission team will begin today at 2:00 p.m. EST.
The New Horizons spacecraft accomplished its primary mission on July 14, 2015, when it performed the first close encounter of Pluto. That flyby revealed that even little Pluto, more than three billion miles from the sun, is an active world with shifting plains, glaciers and mountains that reach up to about 15,000 feet. Hard water ice forms the bedrock on Pluto with softer ices on top, such as nitrogen, carbon monoxide and methane.
The spacecraft’s next target, Ultima Thule, could contain even more surprises. “We hardly know anything about it,” says Alan Stern, principal investigator of the New Horizons mission, at APL.
Ultima Thule was only discovered in June 2014 by the Hubble Space Telescope in an effort to find an additional target for New Horizons in the distant family of bodies beyond Neptune known as the Kuiper Belt, the third region of the solar system. “Beyond the terrestrial planets lie the giant planets, and beyond the giant planets lies the Kuiper Belt,” Stern says.
After discovery by the Hubble Space Telescope, a series of ground observations were carried out to measure Ultima Thule during an occultation—as it passed in front of a background star and blocked out some of the starlight. The object appears to be irregularly shaped, about 20 to 30 kilometers in diameter, and tinted red. What types of ices and rocks constitute the object will provide planetary scientists with the first example of a primordial planetary body orbiting in this distant realm. The instruments on New Horizons will create geologic and compositional maps of Ultima Thule, as well as searching for any rings, debris, or even small satellites orbiting the object.
It may be that Ultima Thule is similar to comets that follow elliptical paths taking them close to the sun, only Ultima was never perturbed and flung inward by a gravitational encounter with Neptune or Uranus. The small body continues to orbit undisturbed on a more circular path than comets, never getting closer than 42 Astronomical Units, or 42 times the average distance between the Earth and the sun.
At the moment, Ultima Thule is little more than a pixel of light on New Horizon’s imaging instruments. Images of the object taken just before the encounter will grow to a few more pixels, transmitted back to Earth at the speed of light in about six hours. The high-resolution images of Ultima Thule are scheduled to be received and released back on Earth on Wednesday, January 2, truly revealing this distant body to the world for the first time.
“Being on the first mission of discovery when points of light become real places almost overnight is an incredibly humbling experience to be a part of,” Stern told Smithsonian.com. “It’s scientifically indescribable. … To have the chance to lead this from the inception through design and build and flight across the solar system, and now to our capstone in the Kuiper Belt, is the product of a lifetime, and it’s something that dreams are made of.”
A full decade ago, paleontologists digging around in the Canadian High Arctic discovered something amazing—a fish whose front fins seemed made for walking. The ancient fish, which lived 375 million years ago, looked a lot like a fish and a bit like a crocodile: it had a flat, broad head, a long, slender body and front fins that the researchers described as “morphologically and functionally transitional between a fin and a limb.”
After analyzing the bones, the scientists, led by Neil Shubin, suggested that the fish, Tiktaalik roseae, could prop itself up on its front fins to help it catch its prey in the river waters of what is now Canada's Ellesmere Island.
When the first Tiktaalik roseae fossil was found in 2004, however, large parts of the organism were missing, including its hindquarters. But now, Shubin and his colleagues are back with a new Tiktaalik fossil. This time they've got a preserved pelvis, and more surprises for the evolution of four-legged propulsion.
In addition to its limb-like front fins, Tiktaalik also had large, mobile rear fins that it used to push itself around in the water. Postmedia News' Margaret Munro reports that, according to the new study, the fish's pelvis was "much bigger than expected"—and indicates that Earth's organisms may have started doing something like walking on four legs much earlier than scientists had thought:
“It looks like this shift actually began to happen in fish, not in limbed animals,” team leader Neil Shubin, at the University of Chicago, says in a summary of the findings....
“This is an amazing pelvis, particularly the hip socket, which is very different from anything that we knew of in the lineage leading up to limbed vertebrates,” co-author Edward Daeschler said in a summary of the findings.
The finding that Tiktaalik had useful back limbs, too, certainly sounds like would have given the fish some advantages, says Jonathan Amos for the BBC:
The fins undoubtedly were employed as paddles to swim, but might also have been used in a leg-like way on occasions.
"Tiktaalik probably had the ability to use those fins as props to move along, using them to push along the shallow bottom, to work its way through plants; and, who knows, maybe it got out of the water briefly if it needed to move over to another watercourse," speculated Dr Daeschler.
"But in no way was it specialised for getting out of the water. It may have had some ability to do that, but everything about its reproduction, its sensory system, its hunting, its breathing - all these things tied it to the water," he told BBC News.
Animals like Tiktaalik roseae can be tricky to think about, and it's easy to misrepresent them as animals that so desperately wanted to walk on land. But, of course, says Berkeley's Understand Evolution, that's not how evolution works:
Tiktaalik was specialized for life in shallow water, propping itself up on the bottom and snapping up prey. The adaptations it had for this lifestyle ended up providing the stepping stones for vertebrates to climb onto dry land — but of course, Tiktaalik was not "aiming" to evolve features for land-living. Tiktaalik was simply well-adapted for its own lifestyle and later on, many of these features ended up being co-opted for a new terrestrial lifestyle.
There was already some contention over the timing of the arrival of four-limbed motion, with some researchers in 2010 suggesting they'd found track marks from a four-legged animal that predated even Tiktaalik. But aside from that, the new discovery can help answer one of the persistent questions in evolution: what good is half a leg?
The movement of tectonic plates that created the Mediterranean Sea and the Alps also sparked the drying of the Sahara some 7 million years ago, according to the latest computer simulations of Earth’s ancient climate.
Though North Africa is currently covered by the world’s largest non-polar desert, climate conditions in the region have not been constant there for the last several million years. Subtle changes in Earth’s tilt toward the sun periodically increase the amount of solar energy received by the Northern Hemisphere in summer, altering atmospheric currents and driving monsoon rains. North Africa also sees more precipitation when less of the planet’s water is locked up in ice. Such increases in moisture limit how far the Sahara can spread and can even spark times of a “green Sahara”, when the sparse desert is replaced by abundant lakes, plants and animals.
Before the great desert was born, North Africa had a moister, semiarid climate. A few lines of evidence, including ancient dune deposits found in Chad, had hinted that the arid Sahara may have existed at least 7 million years ago. But without a mechanism to explain how it emerged, few scientists thought that the desert we see today could really be that old. Instead, most scientists argue that the Sahara took shape just 2 to 3 million years ago. Terrestrial and marine evidence suggest that North Africa underwent a period of drying at that time, when the Northern Hemisphere started its most recent cycle of glaciation.Seen via satellite, the Sahara in North Africa covers an area nearly as large as China. (NASA/Wikimedia Commons)
Now Zhongshi Zhang of the Bjerknes Centre for Climate Research in Bergen, Norway, and colleagues have run simulations of climate change in North Africa over the last 30 million years. Their simulations take into account changes in Earth’s orbital position, atmospheric chemistry and the ratio of land to ocean as driven by tectonic forces. The models shows that precipitation in North Africa declined by more than half about 7 million years ago, causing the region to dry out. But this effect could not be explained by changes in vegetation, Earth’s tilt or greenhouse gas concentrations—leaving tectonic action.
About 250 million years ago, a huge body of water called the Tethys Sea separated the supercontinents of Laurasia to the north and Gondwana to the south. As those supercontinents broke apart and shuffled around, the African plate collided with the Eurasian plate, birthing the Alps and the Himalayas but closing off the bulk of the Tethys Sea. As the plates kept moving, the sea continued to shrink, eventually diminishing into the Mediterranean.
What set off the aridification in Africa was the replacement of the western arm of the Tethys Sea with the Arabian Peninsula around 7 to 11 million years ago. Replacing water with land, which reflects less sunlight, altered the region’s precipitation patterns. This created the desert and heightened its sensitivity to changes in Earth’s tilt, the researchers conclude in a study published today in Nature.
The emergence of the Sahara 7 million years ago would have affected the plants and animals in the region—and possibly the early ancestors of human beings. For instance, Sahelanthropus tchadensis, which may be the earliest member in the human family tree, lived just to the south of the Sahara (in what is now northern Chad) around the time of the transition. Overall, the team writes, the study adds to evidence that changes in precipitation “were fundamental to the evolution and dispersal of hominins in north Africa.”
Blue whales, which can grow to around 100 feet in length, are often touted as the largest animals to have ever existed on earth. But as John Pickrell at National Geographic reports, paleontologists in England recently discovered a bone from an ancient 'sea monster' that seems to have been just as big, hinting at the possibility other ancient sea creatures were just as massive.
In 2016, amateur fossil hunter Paul de la Salle was walking the beach in Lilstock, a town in Somerset in the southwest of England, when he found a large fossil. He believed it belonged to an ichythosaur, a dolphin-shaped carnivorous marine reptile with a long, toothy snout that lived in the oceans during the age of the dinosaurs. He continued to search the area, discovering more pieces of the fossil, which, when fit together, make up a 3.2-foot section of jawbone.
De la Salle got in touch with ichthyosaur experts Dean Lomax at The University of Manchester and Judy Massare, professor emerita of geology at SUNY College at Brockport. According to a press release, the researchers dated the bones to 205 million years ago, and estimate that in life the Lilstock ichthyosaur would have been up to 85 feet long, edging well into blue whale territory. A description of the fossil appears in the journal PLOS One.
“This bone belonged to a giant,” Lomax tells Reuters. “The entire carcass was probably very similar to a whale fall in which a dead whale drops to the bottom of the sea floor, where an entire ecosystem of animals feeds on the carcass for a very long time. After that, bones become separated, and we suspect that's what happened to our isolated bone.”
This new specimen is about 25 percent larger than the previous largest ichythyosaur, a 69-foot-long creature including half a skull, backbone ribs and part of the tail called Shonisaurus sikanniensis found in British Columbia, reports Laura Geggel at LiveScience.
“A comparison with the back of the Shonisaurus jaw indicates that our specimen is larger,” Massare, a co-author of the study, tells Geggel. “But we know much less about it because it is just one bone.”
As Pickrell reports, the find has led the team to reassess other fossils found along the English coast. In particular, they reexamined a group of large bones found in cliffs near the village of Aust in Gloucestershire, England. These were previously interpreted as being limbs from terrestrial dinosaurs, but the classification never perfectly lined up.
“We compared it with these Aust bones, and as soon as I saw it in person, my jaw just hit the floor,” Lomax tells Pickrell. “I realized this was a giant ichthyosaur and the biggest thing ever found in the U.K.” The Aust fragments may have once belonged to creatures even larger than the Lilstock beast.
Paleontologist Darren Naish from the University of Southampton, who has studied the Aust bones and come to the same conclusion, tells Pickrell that these new finds are astonishing and agrees that they suggest that these ichthyosaurs neared or even exceeded modern baleen whales in size.
If that’s the case, it’s a big deal. Many researchers are investigating the question of how baleen whales got so big. Studies suggest for the whales, their massive size is a relatively recent phenomenon, perhaps fostered by giant clouds of krill that lived on the edges of ice sheets during the Ice Ages. But why certain ichthyosaur species would grow to such mammoth proportions remains a matter of speculation.
Ichthyosaurs appeared during the start of the Triassic, some 250 million years ago. Though they initially lived along coasts, they eventually moved to deeper water. At their height, they filled many niches, from ambush predator to suction feeder and were among the most successful animals in the oceans. But about 90 million years ago, almost 25 million years before the dinosaurs disappeared, ichthyosaurs died out. Researchers are currently trying to understand what drove the once-plentiful sea reptiles to extinction.
In February 1971, Apollo 14 landed on the moon carrying astronauts Alan Shepard and Edgar Mitchell to the lunar surface while Stuart Roosa circled above in the Command Module. The mission was the third to land on the moon, touching down near Cone Crater. The two moonwalkers took photos of the lunar surface, conducted geologic and seismic studies, and Al Shepard, the first American in space, affixed a six iron golf clubhead to a lunar excavation tool and hit two golf balls into the weak gravity of the moon.
The crew also brought back almost 100 pounds of lunar samples. Nearly five decades later, one of the rocks in the Apollo 14 haul, a 20-pound, basketball-sized chunk of lunar material officially known as 14321, has recaptured the attention of planetary scientists. According to a recent study in Earth and Planetary Science Letters, a large portion of 14321 may have formed not on the moon, but on Earth some four billion years ago, which would make it the oldest known rock from our planet.
The rock 14321 is a breccia, or a conglomeration of rocks and minerals all cemented together in a mosaic-like pattern. Most of the rock fragments, or clasts, are dark in color, according to Michael Greshko at National Geographic, resembling lunar material. But one part of 14321 is brighter than the rest, similar to igneous rocks such as granite found in abundance on Earth.Rock fragment 14321 collected on the moon during Apollo 14. (NASA)
A team of lunar scientists, led by the Center for Lunar Science and Exploration (CLSE), the Universities Space Research Association (USRA) and the Lunar and Planetary Institute (LPI), sampled the brighter clast of 14321 to analyze the minerals of the rock and attempt to determine its origin. The researchers examined zircon, an incredibly resilient mineral, as well as feldspar and quartz from the rock sample, according to Mike Wall at Space.com. They found that the bright piece of 14321 must have formed in relatively cool, oxygen-rich magmas at high pressures.
On the moon, these conditions are rare. It’s possible that the bright part of 14321 formed more than 100 miles below the lunar surface in a water-rich pocket of magma, according to National Geographic. But the impact that created Cone Crater—initially thought to have excavated rock 14321 from beneath the lunar surface—only pulled material up from about 45 miles down.
A more likely explanation, according to the study, is that the clast of 14321 formed on Earth 4 to 4.1 billion years ago, about 12 miles below the terrestrial surface where temperatures, pressures and oxygen levels match the formation conditions of the rock. Early Earth was repeatedly pummeled by space rocks, such as asteroids and meteorites, that pushed 14321 closer and closer to the surface over time, until a collision sent it hurling toward the moon where it was buried once more and partially melted. Then another impact about 26 million years ago pushed it to the lunar surface where it sat until Al Shepard walked by and picked it up.
“It is an extraordinary find that helps paint a better picture of early Earth and the bombardment that modified our planet during the dawn of life,” planetary scientist David Kring, who is the principal investigator at CLSE, says in a press release.An artistic rendering of the Hadean Earth when the rock fragment was formed. Impact craters, some flooded by shallow seas, cover large swaths of the Earth’s surface. The excavation of those craters ejected rocky debris, some of which hit the moon. (Simone Marchi)
For a period of about 300 million years, between 3.8 and 4.1 billion years ago, the early Earth and moon were peppered with asteroid impacts, known as the Late Heavy Bombardment. During this time of the Hadean eon—the first geological eon in Earth’s history—Earth and the moon are known to have traded a significant amount of material. As impactors slammed into Earth’s surface, rocks and debris were catapulted into space, some of which rained down on the early moon, which was three times closer than it is today.
As Earth and the moon cooled into the worlds we know today, rock 14321 was apparently flung to the moon, thereafter preserved in the airless, undisturbed, geologically inert lunar environment. While some zircon minerals discovered on Earth, in Western Australia’s Jack Hills, may be as old as 4.4 billion years old, these are “individual, contextless crystals,” lead author of the new study Jeremy Bellucci, a geologist at the Swedish Museum of Natural History, tells National Geographic.
If part of lunar rock 14321 indeed formed on Earth, it represents the oldest known rock from our planet, making the lunar voyage some four billion years before Al Shepard, who happened to pick it up between golf swings.
After a year of complete isolation, six strangers inside a cramped, uninsulated dome on the side of a Hawaiian volcano have emerged. No, this isn't a tale of survival. The crew members just completed an experiment to test whether humans could take the psychological rigors of living on Mars.
As Space.com's Calla Cofield reports, the six crew members were participating in the Hawaii Space Exploration Analogue and Simulation project, or HI-SEAS. They lived together during the mock mars mission in a self-sufficient habitat for 12 months, limiting their contact with family and friends and spending their days in isolation that, at times, proved challenging.
HI-SEAS is all about preparing Earthlings for long-duration life on Mars. Since the planet is nearly 34 million miles away, it won't exactly be easy for red-planet inhabitants to interact with folks back home. Each HI-SEAS mission pits a crew of six against the isolation and lack of stimulation of a manmade habitat that simulates how people might live in on Mars. Resupply missions were rare, and participants had to don spacesuits when they left the dome.
As Nadia Drake reports for National Geographic, it's a life that would challenge the most self-sufficient person. Not only is there a 20-minute communication delay (simulating similar delays that might exist on Mars), but conditions in the 1,200 square-foot dome are tough. Crew members must survive everything from hot and cold temperatures to freeze-dried foods, not to mention the grueling reality of being isolated from friends and family. Drake notes that at least two of the six people inside experienced family deaths during their isolation. And the crew members had to improvise everything from Yahtzee games to dance-offs to keep their morale up. (For a further glimpse of daily life inside the dome, check out Calla Colfield's travelogue on Space.com.)
The concept of sending people to planet-like areas on Earth to train is as old as the space program itself. But HI-SEAS differs from some other variations of what are called "terrestrial analogues" within the world of space travel. Unlike simulations that, say, send astronauts underwater to mimic low-gravity movement or pit future crew members against caves or desert landscapes, HI-SEAS was specifically designed to study the psychology of space travel. Given that the team experienced several mini-emergencies, like when their water system broke, it offered analysts a rich way to study not just how strangers behave when they're thrown together in a strange environment, but how they interact once they've been given a challenging mission to complete.
The yearlong mission was the third for the group, which is funded by NASA's Behavioral Health and Performance initiative and administered by the University of Hawai'i and Cornell University. In the spirit of exploration, the crew was tracked with everything from motion trackers to cameras while they were in the dome. Now that they're out, they'll be debriefed and sent home—to a daily life that will presumably be forever transformed by all that time in the dome.
So the idea of living in total isolation with strangers may still not seem that appealing. (If it does, don't worry—HI-SEAS is recruiting for another mission now.) But when humans do finally head to the red planet, they'll take the lessons of HI-SEAS—Yahtzee, broken baths and all—along with them. When it comes to science, what's a little inconvenience now and then?
Memory is a notoriously slippery ally. It’s alarmingly easy to purposely distort recall, even in people with the unusual ability to remember minute details, going back to childhood. Absent manipulation, it is still extraordinarily difficult to be a reliable witness. Studying faults in memory, though, can reveal how it functions—even in such seemingly simple organisms as bees.
The latest work, published in Current Biology, looks at how bees, like humans, can be prone to false memories. Previously, researchers had manipulated the electrical zings of specific mouse brain cells to give rodents a false memory of an event that never happened. But naturally occurring false memory hasn’t been shown in non-humans before.
Honeybees and bumblebees are favorite subjects in the study of learning and memory because they rely on color, scent and taste to help them find flowers and, therefore, food. They forage, so they are also good at using sensory cues to map their surroundings. In the new study, U.K.-based researchers tested bumblebees’ false memory formation using differently colored fake flowers.
The researchers first trained their bees (Bombus terrestris) to know which flowers contained a droplet of nectar. All the bees learned that two types of flowers contained a reward: For example, for one group tested, the flowers worth visiting were solid yellow ones and flashy ones sporting alternating rings of black and white. (Other bee groups learned different patterns, such as a black grid over white, to avoid any sort of innate bee preferences that might obscure the results.) Then, the researchers gave the insects a chance to choose from a wide array of different flowers.
Right after they had been trained, the bees knew exactly which flowers to visit—the solid yellow and the black and white ones. But when they were tested three days later, they started to gravitate toward a third type of flower that hadn’t been present during training.
This flower represented a merged version of the two they had been trained to recognize. For our example group, yellow and white concentric circles now seemed most exciting. As the experimental trials proceeded on that third day, the bees apparently got more and more mixed up: Just 34 percent preferred the merged blooms during the first ten trials, but 50 percent did during the last ten. These bees seemed convinced that the hybrid fake flower was the one they remembered carrying nectar.
The preference change shows that bumblebees are vulnerable to a memory error that also crops up in people, the researchers write. Research in humans shows that we make similar merging mistakes when asked to recall faces, nonsense words and simple sentences.
Since the bees and humans do fine with tests right after training, the problem isn’t with short term memory, but when the memory is moved into long term storage. During that move, information is lost and details glossed over. (The "mind palace" that Sherlock Holmes uses is a strategy that to try and avoid just that.)
This tendency to come up with false, merged memories isn’t a bad thing, though. It’s proof that our memory system is flexible. "There is no question that the ability to extract patterns and commonalities between different events in our environment [is] adaptive," Lars Chittka of Queen Mary University of London says in a press release. "Indeed, the ability to memorize the overarching principles of a number of different events might help us respond in new situations. But these abilities might come at the expense of remembering every detail correctly." His team has also found that people who are good at learning to classify objects are particularly susceptible to this kind of memory glitch.
It’s probably good for bees (and other creatures) to make these kind of "mistakes" because they’re likely to at least investigate objects or locations they’ve never seen before. If it is anything like something they do remember seeing, it might worth checking out. After all, unfamiliar flowers carry nectar, too.
Any report on invasive species is bound to have bad news, it seems, and a new report from the U.S. Geological Survey analyzing the threat from nine giant snake species is possibly even worse because we're talking about GIANT SNAKES (and I'm not generally scared of snakes). These snakes have already made their way here to the United States—as pets or hidden in cargo (Snakes on a Plane was NONFICTION?! -Ed.), usually—and pose a threat to the ecosystems where they might or have already become established. There are five identified as high risk (details below) and four medium risk species (reticulated python, DeSchauensee’s anaconda, green anaconda, and Beni anaconda). There are no low risks, the USGS notes, because all nine "share several traits that increase their risk of establishment, increase the damage they might do, or make eradication difficult." (Worryingly, the report notes that there are no control tools for eradicating these species once these have become established.)
Specifically, these snakes:
1. Grow rapidly to a large size (some individuals of these species surpass 20 feet in length and 200 pounds in weight);
2. Are habitat generalists (they can live in many kinds of habitats and have behaviors that allow them to escape freezing temperatures);
3. Are dietary generalists (can eat a variety of mammals, bird, and reptiles);
4. Are arboreal (tree-living) when young, which puts birds and arboreal mammals such as squirrels and bats at risk and provide another avenue for quick dispersal of the snakes;
5. Are tolerant of urbanization (can live in urban/suburban areas);
6. Are well-concealed “sit-and-wait” predators (difficult to detect, difficult to trap due to infrequent movements between hiding places);
7. Mature rapidly and produce many offspring (females can store sperm and fertilize their eggs—which in some of these snakes can number more than 100—when conditions are favorable for bearing young);
8. Achieve high population densities (greater impact on native wildlife); and
9. Serve as potential hosts for parasites and diseases of economic and human health significance. Had they not possessed these features, they might have constituted a low risk.
The five high risk species:
Burmese python (Python molurus) Native to: Southeast Asia, from Pakistan and India to China and Vietnam to Indonesia Size: on average, grows to 18 feet and 160 pounds Eats: terrestrial vertebrates, including lizards, birds and mammals; has been known to attack and kill humans U.S. states with suitable climate: Alabama, Arkansas, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, Oklahoma, North Carolina, South Carolina, Texas Already established in: Florida, in the Everglades
Northern African python (Python sebae) Native to: central Africa from the coasts of Kenya and Tanzania to Mali and Mauritania, and north to Ethiopia and Eritrea; in arid regions, only near permanent water Size: a typical adult is around 16 feet Eats: antelopes, warthog, porcupine, caracal, birds, fish, crocodiles, lizards, frogs U.S. states with suitable climate: southern half of Florida, southern tip of Texas, Hawaii May already be established in: southern Florida
Southern African Python (Python natalensis) Native to: ranges from Kenya southwest to Angola and south through Namibia and eastern South Africa Size: a typical adult is around 16 feet, but can grow bigger than the Northern African python Eats: antelopes, warthog, porcupine, caracal, birds, fish, crocodiles, lizards, frogs U.S. states with suitable climate: southern half of Florida, along much of the southern border of Texas, Hawaii
Boa constrictor (Boa constrictor) Native to: much of central and South America, from Mexico to Argentina Size: adults are around 13 feet long Eats: mammals, birds, lizards, fish U.S. states with suitable climate: Arizona, Florida, Georgia, Hawaii, New Mexico, Texas Already established in: southern Florida
Yellow anaconda (Eunectes notaeus) Native to: Argentina, Bolivia, Brazil, Paraguay, Uruguay Size: 10 to 12 feet on average Eats: fish, turtles, aquatic birds, rodents U.S. states with suitable climate: Florida, southeast Georgia, southern and eastern Texas, southern California, Hawaii
Editor's Note: An earlier version of this article mistakenly identified the snakes in the photo as boa constrictors. They are ball pythons. The error has been fixed.
Image by Courtesy of Flickr user Nicovangelion. Boa constrictors (original image)
Image by Courtesy of Flickr user aehack. A Burmese python (original image)
In paleontology, you’re always most likely to find something on the very last day of the season. That’s what happened in 2007, when a multi-institution team of paleontologists was poking around Patagonia’s Huincul Formation looking for one last find. “It’s the last day, you’d better find something good!” Field Museum paleontologist Pete Makovicky joked to the team. Then Akiko Shinya, his lab preparator, did just that. A few moments after Makovicky’s command, Shinya found the first signs of an unusual dinosaur with an unexpected connection to the celebrated Tyrannosaurus rex.
The new dinosaur, described today by Makovicky and coauthors in the journal PLOS ONE, only survived in pieces: part of the spine, belly ribs, tail, hips, hind limbs, and arms were recovered. However, taken together, these parts represent a species of dinosaur not seen before in the approximately 94-million-year-old boneyard of northern Patagonia. The researchers have named it Gualicho shinyae, with the species name honoring Shinya for her 11th hour discovery. Gualicho refers to a Spanish name for a local goddess later reinterpreted as a wellspring of bad luck. “The name was chosen to reflect the difficult circumstances surrounding the discovery and study of the specimen,” the paleontologists write, “and its contentious history following excavation.”
Gualicho’s most striking feature is one some might see as its most pathetic: Like T. rex, the arms of Gualicho are short and spindly, with only two prominent fingers. The remnant of the third finger is reduced to a tiny splint. This wouldn’t be surprising in a tyrannosaur, but Gualicho is no T. rex: the dinosaur belonged to a group that included Allosaurus and its kin—predators that usually have been found with longer arms and three functional fingers. No one had found an allosaur with arms like this before, making the find a puzzling one for paleontologists. “The reduction of the hand and number of digits is particularly striking,” says University of Southern California paleontologist Michael Habib, who was not involved in the research.
So apparently arm day at the gym was not a thing for Gualicho, just as it wasn’t for Tyrannosaurus, the stubby-armed Carnotaurus, and other predatory dinosaurs that independently evolved abbreviated forelimbs. The question facing paleontologists is: why so small?Tiny arms are bigger than just T. rex (pictured). (Jurassic Park / Universal Studios)
Smaller arms and hands in dinosaurs like Gualicho, Tyrannosaurus, Carnotaurus, and others, says University of Maryland paleontologist Thomas Holtz, Jr., “is almost certainly due to the shared reduction in function in said limbs.” Thinking in terms of how these dinosaurs hunted, Holtz says that this almost certainly marks “a shift to head-only prey acquisition and dispatch.”
That is, long arms with meathook claws may not have been much benefit to Gualicho and other carnivores. “The forelimbs of most theropods likely had only limited function,” Habib says, meaning that smaller forelimbs, while silly-looking, might not have been a disadvantage. Quite the opposite: “Reducing the arms was probably ‘beneficial’ in that they got them out of the way of the more powerful jaws,” says Holtz, who was also not involved in the research. More than that, Habib points out that “The most obvious advantage to having short arms for a terrestrial carnivorous dinosaur is the associated increase in available space for neck muscles to anchor to the torso.”
In other words: smaller arms, better bite.
Considering the prevailing winds, David J. Smith figured the air samples collected atop a dormant volcano in Oregon would be full of DNA signatures from dead microorganisms from Asia and the Pacific Ocean. He didn’t expect anything could survive the journey through the harsh upper atmosphere to the research station at the Mount Bachelor Observatory, at an elevation of 9,000 feet.
"I thought we would basically be collecting nothing but dead biomass," says Smith, a research scientist with NASA's Ames Research Center.
But when his team got to the lab with the samples, taken from two large dust plumes in the spring of 2011, they discovered a thriving bunch of hitchhikers. More than 27 percent of the bacterial samples and more than 47 percent of the fungal samples were still alive.
Ultimately, the team detected about 2,100 species of microbes, including a type of Archea that had only previously been isolated off the coast of Japan. “In my mind, that was the smoking gun,“ Smith says. Asia, as he likes to say, had sneezed on North America.
Microbes have been found in the skies since Darwin collected windswept dust aboard the H.M.S. Beagle 1,000 miles west of Africa in the 1830s. But technologies for DNA analysis, high-altitude collection and atmospheric modeling are giving scientists a new look at crowded life high above Earth. For instance, recent research suggests that microbes are hidden players in the atmosphere, making clouds, causing rain, spreading diseases between continents and maybe even changing climates.
"I regard the atmosphere as a highway, in the most literal sense of the term," Smith says. "It enables the exchange of microorganisms between ecosystems thousands of miles apart, and to me that’s a more profound ecological consequence we still have not fully wrapped our heads around."
Airborne microbes potentially have huge impacts on our planet. Some scientists attribute a 2001 foot-and-mouth outbreak in Britain to a giant storm in north Africa that carried dust and possibly spores of the animal disease thousands of miles north only a week before the first reported cases.
Bluetongue virus, which infects domestic and wild animals, was once present only in Africa. But it's found now in Great Britain, likely the result of the prevailing winds.
Scientists examining the decline of coral reefs in near-pristine stretches of the Caribbean are pointing at dust and accompanying microbes, stirred up during African dust storms and carried west, as the culprit. A particular fungus that kills sea fans first arrived in 1983, researchers say, when a drought in the Sahara created dust clouds that floated across the Atlantic.
In west Texas, researchers from Texas Tech University collected air samples upwind and downwind of ten cattle feedlots. Antibiotic resistant microbes were 4,000 percent more prevalent in the downwind samples. Philip Smith, an associate professor of terrestrial ecotoxicology, and Greg Mayer, an associate professor of molecular toxicology, said the work establishes a baseline for further research.
They have completed a study of viability to be released in early 2016 and want to look at the questions of how far the particles travel and whether resistance can be transmitted to native bacteria. Antibiotics, Mayer notes, existed in nature long before humans borrowed them. But what happens when they are concentrated in places, or spread on the wind?
What's clear is there are far more viable microbes in far more inhospitable places than scientists expected.
Researchers from the Georgia Institute of Technology, supported by a NASA research grant, examined air samples collected by a plane flying during hurricanes miles above Earth. They found that living cells accounted for about 20 percent of of the storm-tossed microbes.
"We were not expecting to find so many intact and alive bacterial cells at 10,000 meters," says Kostas Konstantinidis, a microbiologist at the Georgia Institute of Technology.
Konstantinidis and his team are particularly interested in how microbes contribute to cloud formation and precipitation. Nuclei in bacteria in the air initiate condensation. Some scientists now believe microbes may play a major part in meteorology. "They have great potential for affecting cloud formation and the climate," Konstantinidis adds.
Meanwhile, Smith is intrigued by how microbes survive or perhaps repair themselves after days-long journeys in the harsh radiation of the upper atmosphere. A NASA project, EMIST (Exposing Microorganisms in the Stratosphere), spearheaded by Smith, has twice carried spore-forming bacteria to 125,000 feet above the New Mexico desert on a balloon to investigate their survival.
For NASA, the work is related to planetary protection. If a spacecraft contaminated with Earth bacteria reaches Mars—which has conditions similar to Earth's stratosphere—and the bacteria survive, it could complicate our search for evidence of life on Mars or even kill off native microbes, if they exist.
But it also has far broader possibilities. Like earlier researchers who explored the rainforest searching for wonder drugs, researchers may one day find remedies in the miniscule inhabitants of the atmosphere. Maybe atmospheric bacteria can offer us the ultimate sunscreen and protection against radiation.
“It's extraordinary that an organism that can survive such a harsh environment is in many cases a single cell," Smith says. “How are they doing what they are doing?”A scientific balloon holds NASA's Exposing Microorganisms In The Stratosphere (E-MIST) experiment shortly before launch Aug. 24, 2014. The experiment exposed Earth bacteria to the upper atmosphere to learn whether they could survive the harsh conditions. (NASA)
In 1910, Bavarian aristocrat and paleontologist Freiherr Ernst Stromer von Reichenbach set out for the Egyptian desert. Despite a cholera outbreak on his ship and a world on the brink of war, he persisted, reaching his destination and obtaining permission to excavate an area roughly 200 miles outside of Cairo. In the months that followed, he and Austrian fossil hunter Richard Markgraf unearthed the remains of dozens of turtles, crocodiles, marine reptiles and dinosaurs. Then, in 1912, they made the discovery of a lifetime.
In rocks dating back to the Late Cretaceous period, they detected the partial skeleton of a massive unknown dinosaur. Its features were peculiar, including a 15-foot crocodile-like jaw, large conical teeth and enormous spines rising five feet from its back, suggesting a hump or sail. All signs indicated that this was an apex predator similar to T-Rex, but that would make it one of at least two top-of-the-food-chain dinosaurs known to exist at the time. How could one ecosystem support so many terrifyingly large carnivores? This question became known as Stromer’s Riddle and would remain unsolved for decades.
Stromer named the dinosaur Spinosaurus aegypticis, or the Egyptian Spine Lizard, and rose to fame in the wake of the discovery. Tragically, this fame was short-lived. Stromer was openly critical of the Nazi party, and Karl Beurlen, head of the Bavarian museum that housed the Spinosaurus fossils, was an ardent Nazi supporter. Come World War II, Beurlen ignored Stromer's pleas to move the collection from Munich to the safety of caves and salt mines due to politics, and the fossils were destroyed by the Allied forces in a 1944 bomb raid of the city. Stromer's family also suffered. Two sons perished on the front lines, and one was captured by the Soviets, unable to return until after the war. Stromer died a broken man in 1952, and the Spinosaurus with him. All that remained were his notes and sketches, as well as photographic records donated to the renovated museum by his surviving son.
As the world recovered from the effects of war, small pieces of Spinosaurus skeletons were discovered around the world, and theories about Spinosaurus' place in the ecosystem began to emerge. However, due to the lack of a complete specimen, Spinosaurus remained a mystery.
Not until a series of chance encounters by paleontologist Nizar Ibrahim in the late 2000s did Spinosaurus once again enter the limelight. While conducting research in the fossil-rich Kem Kem Beds on the border of Morocco and Algeria in 2008, Ibrahim crossed paths with a Bedouin fossil hunter who showed him a collection of dinosaur bones housed in a distinctive purple sediment with yellow stripes. The following year at the Natural History Museum in Milan, Ibrahim was examining a newly discovered partial skeleton that appeared to be the same species as Stromer’s Spinosaurus when he noticed the same purple-yellow sediment clinging to them. These fossils, he thought, could belong to the same dinosaur.
Ibrahim returned to Erfoud, Morocco, to locate the Bedouin. However, he couldn’t remember the fossil hunter’s name or where he came from, only that he was wearing white clothes and had a mustache. The search seemed fruitless until one day, four years after visiting Milan, Ibrahim saw a man in white with a mustache walk by the café where he was meeting fellow scientists. It was the Bedouin fossil hunter. Catching up to him, Ibrahim convinced the hunter to take them to the place where the fossil was recovered.
Now Ibrahim was able to put the fossils in context, deducing that the area in which the Spinosaurus was found was once a lush plain over which rivers meandered between the Early and Late Cretaceous periods. Combining scans of new finds with specimens in other collections, he was also able to create a detailed digital reconstruction of the dinosaur, offering new insight into its way of life. According to his reconstruction, an adult Spinosaurus would have measured 50 feet long, surpassing the T. Rex by almost 10 feet. Additionally, the dinosaur would have had a barrel-shaped torso like modern whales and dolphins and short, stumpy hind limbs that would have shifted its center of gravity forward, making it difficult to walk effectively on two legs. Instead, its front legs may have been used to walk on all fours on land and its hind limbs to paddle in the water. Perhaps Spinosaurus was not only largest carnivorous dinosaur that ever lived, but also the only known truly aquatically adapted one.
Thanks to that chance encounter at the café, today we have a potential answer to Stromer’s Riddle. Spinosaurus was able to coexist with other apex predators due to “ecological niche partitioning.” Rather, they lived in different environments. According to this theory, Spinosaurus represents a transition between the terrestrial and aquatic environments. However, it is important to acknowledge that Ibrahim’s reconstruction and interpretations are still being debated. Paleontological research is ever evolving and new discoveries may soon provide a more complete picture of Stromer's once-lost dinosaur.
This article is adapted from the "Introduction to Paleontology" video series by The Great Courses Plus.
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Orchids can hide. Members of this diverse family of plants, known for their wildly attractive flowers, have long been recognized for their ability to enter extended periods of dormancy—sometimes for a year or longer. The plants take refuge underground, and with no leaves and no need for photosynthesis, the orchids rely on fungi for the nutrients they need to survive.
Scientists have long puzzled over what prompts the plants to switch from a state of dormancy and send up shoots. Now, a new study by a group of scientists from the Smithsonian Environmental Research Center in Edgewater, Maryland, explains how concentrations of certain fungus in the soil cause one North American species of orchid, the small-whorled pogonia, to awaken.
“This is an extremely rare orchid and as rare as it is, it's not as rare as we thought because it spends a lot of time hiding out underground,” says Smithsonian ecologist Melissa McCormick, one of the authors of the paper. “We had done some previous research into orchid mycorrhizal fungi. . . we were interested in whether the abundance of fungi in the soil was affecting not just where they are, but also when they emerge.”
The fungi turned out to be the key. Most orchids form symbiotic partnerships with particular species of fungi in order to survive. Orchid seeds lack the starchy endosperm that helps to feed the new sprouts of many other types of plants. Instead, the seeds depend on mycorrhizal fungus in the soil. They only send a shoot up when it is time to flower and reproduce. The small-whorled pogonia has this relationship with a mycorrhizal fungus in the Russulaceae family.Smithsonian researcher Melissa McCormick says there is a link between the dormancy period of the small-whorled pogonias and the amount of a specific type of fungus in the soil. (Dennis Whigham)
McCormick analyzed the DNA of soil samples collected immediately adjacent to wild small-whorled pogonias, and used that data to calculate how much Russulaceae hyphae was present in the soil at each site.
When McCormick and the four other scientists involved with the research compared the abundance of Russulaceae in the soil with the frequency that the dormant pogonias awoke and sent up shoots, they found a clear relationship: Greater populations of the fungus meant that the rare pogonias were more likely to emerge. In other words, more of the right fungus in the soil helps the orchid to come out of dormancy more often.
In the past, without the ability to analyze the DNA of a sample, it wasn't practical to calculate exactly how much of any one fungus was present. Even under a microscope, a lot of fungi look very similar. “In a sample of soil the size of a lima bean you have probably several hundred species of fungus,” McCormick says.
“This fungal aspect of all this work has been known since Darwin's time,” says Dennis Whigham, senior botanist at the Smithsonian Environmental Research Center and a co-author of the study. “But only in recent years have we been able to really go after it and look at the DNA of the fungi to see what they are.”When fungi come into contact with an orchid root, they form pelotons, or coiled balls, that the orchid uses for nutrients. (Liz Kabanoff)
Some of the showiest orchids from tropical regions have lent the impression that orchids are an exotic, tropical group of plants. But orchids are actually very widespread, even in the United States. “We have over 200 species and they occur in every state,” Whigham says. “About 60 percent of them are in trouble somewhere that they occur.”
The decline of many populations of American orchids prompted Whigham and others to help create the North American Orchid Conservation Center, based out of the Smithsonian Environmental Research Center. The center works with around 50 collaborators to preserve habitats and to bank seeds and samples of mycorrhizal fungi, and conduct studies like this one.
What does the fungus get out of this relationship with the orchid? Probably not much.
“All terrestrial plants on Earth have interactions with fungi,” Whigham says. Those partnerships are called 'mutualistic.' But almost all of the evidence indicates that in a fungi-orchid relationship, the orchid is a very needy partner.
A chance encounter in the forests of Bayfield County, Wisconsin, has led scientists to a startling realization: As Jon Martin, a forestry professor at the state’s Northland College, discovered after pointing his ultraviolet flashlight toward a flying squirrel feasting at a bird feeder, the gliding creature’s fur glows a fluorescent bright pink under the right conditions.
To determine whether this phenomenon was merely a one-time anomaly, Martin recruited the help of several Northland colleagues. Next, Jake Buehler writes for National Geographic, the researchers traveled to the Science Museum of Minnesota and Chicago’s Field Museum, where they analyzed 135 squirrel skins—including those of both flying and non-flying specimens—under visible and ultraviolet light.
Time and again, the scientists report in the Journal of Mammalogy, the team found that members of the Glaucomys genus, also known as New World flying squirrels, emitted that same telltale pink glow.
“The fluorescence was there in the Glaucomys from the 19th to 21st century, from Guatemala to Canada, in males and females, and in specimens collected in all seasons,” senior study author Paula Spaeth Anich, a biologist at Northland, tells National Geographic. In fact, all but one of the Glaucomys specimens studied revealed a fluorescent shimmer.
Significantly, Newsweek’s Katherine Hignett notes, New World flying squirrels were the only specimens that appeared to boast this unusual coloring. Although the researchers tested additional species, such as the eastern gray squirrel, the fox squirrel and the American red squirrel, none yielded the results seen amongst members of the three Glaucomys species.
Technically speaking, fluorescence refers to the luminous glow released by a substance absorbing light or another form of electromagnetic radiation. As the team notes in the study, ultraviolet fluorescence has previously been recorded in plants, marine and terrestrial invertebrates, arachnids, and birds.
In mammals, however, the phenomenon has proven far more elusive. Prior to these new findings, fluorescence had only been observed amongst members of the Didelphidae marsupial family, which consists of about two dozen species of American opossums.
Flying squirrels and opossums don’t appear to have much in common, Buehler explains for National Geographic. They’re not closely related, they live in different ecosystems and they follow distinct diets. Still, the two do share one major characteristic: Both are nocturnal, whereas flying squirrels’ non-flying counterparts are more active during the day.
There are an array of potential explanations for flying squirrels’ fluorescence, study co-author Allie Kohler, a graduate student at Texas A&M University who spent her undergraduate years at Northland, tells Newsweek’s Hignett. It’s possible the glow helps squirrels recognize each other in low-light situations, or perhaps ward off predators.
Then again, Kohler says, “This trait could just be a cool color they happen to produce.”
Speaking with National Geographic’s Buehler, Anich details several additional areas of interest, including night-time perception and communication, navigation in snowy environments, and camouflage or mimicry.
Further testing, particularly of other flying squirrel species spread out across the globe, will better elucidate the team’s initial findings, but as Anich points out, the most enticing question the research raises is whether other animals, completely unbeknownst to humans, also possess snazzy fluorescent shimmers.
Anich concludes, “The lesson is that, from our diurnal primate standpoint, we are overlooking many aspects of animal communication and perception that happen at twilight and night-time.”
For baby birds learning how to fly, it takes some practice, positive reinforcement and sometimes a bit of a push. As we know, our feathered friends are survivors of dinosaurs, ironically a terrestrial species that couldn’t fly yet called theropods. Instead, pterosaurs were the kings and queens of the sky during the time of the dinosaurs, but these winged-reptiles bear no relation to modern birds.
Another ability that sets pterosaurs apart could be the ability to fly from the moment they cracked open their shell—little to no parental involvement needed, according to a new study in the Proceedings of the Royal Society B.
Previous research had concluded that pterosaurs probably learned to fly like today’s birds. Observations of prehistoric embryos found that they had poorly developed wings, meaning they likely needed some help from mom or dad until they reached nearly full size. But Cara Giaimo at The New York Times reports the current study had a wealth of new data to analyze that led them to reach the opposite conclusion.
In 2017, paleontologists unearthed a pterosaur colony from the species Hamipterus tianshanensis that was covered with mud 100 to 145 million years ago during floods in Jinzhou, China. Not only were there hundreds of fossilized bones from adults and juveniles, there were also 300 ancient eggs, including 16 with embryos at various stages of development.
Paleobiologists David Unwin of the University of Leicester and Charles Deeming of the University of Lincoln suspected there were enough samples to accurately chart out the development of pterosaur embryos. Unwin tells The New York Times that previous attempts to map the development process had been “kind of ad hoc — just look-at-it-and-guess.”
The duo and their team carefully examined the Jinzhou embryo fossils along with others recently found in China and Argentina. Previous research had assumed that the Jinzhou embryos were all at a similar stage of development. But after analyzing egg size and shape, limb length, and other age markers, they found the embryos were at various stages of development—from freshly laid to close to hatching.
They also looked at data from juveniles of nine other pterosaur species as well as modern crocodiles and quails to understand the sequence in which their bones harden. The team’s conclusion is that the little pterosaurs, known as flaplings, came out of their shells with the right proportions and strong enough bones to let them take to the skies.
“The extraordinary thing about those embryos is they have a set of bones that in many respects match those of adults in terms of proportions," Unwin tells Chelsea White at New Scientist. “When they come out of the egg, they are like mini-adults.”
One of the strongest pieces of evidence that the pterosaurs were precocious fliers is the fact that their wing bone—equivalent to the middle finger in humans and an important bone for flying—hardens very early. In most vertebrates, it’s one of the last bones to ossify.
“It’s extremely unlikely that they would equip themselves with a flight apparatus if they were not going to use it,” Unwin tells Giaimo. “What do you need mummy and daddy for if you can do everything yourself?”
David Martill, paleobiologist at the University of Portsmouth who was not involved in the study, tells Ryan F. Mandelbaum at Gizmodo that the interpretation is solid. “That paper was super,” he says. “If you look at flying animals, even precocious birds, their wing skeletons aren’t as developed. Bats’ aren’t as developed. Pterosaurs, they’re developed with the same aspect ratio of adults.”
But not everyone thinks the tiny pterosaurs were born air-worthy. Kevin Padian, museum curator at the University of California, Berkeley, tells New Scientist that there is an important piece of the flight puzzle missing: muscles. He points out that even precocial birds can only support about 10 percent of their own bodyweight right out of the egg.
“It is quite a stretch to assume that hatchling pterosaurs could support 100 per cent of the body mass in the air, especially with no data on muscle mass of hatchlings,” Padian says.
Unwin points out that this study makes one thing clear: Pterosaurs developed differently than modern birds and bats, making them an imperfect comparison. “It’s that sheer alienness of pterosaurs that is really fascinating about them,” he tells The New York Times’ Giaimo. “These were creatures that were really different than anything that’s around today.”
From around 420 to 350 million years ago, when land plants were still the relatively new kids on the evolutionary block and “the tallest trees stood just a few feet high,” giant spires of life poked from the Earth. “The ancient organism boasted trunks up to 24 feet (8 meters) high and as wide as three feet (one meter),” said National Geographic in 2007. With the help of a fossil dug up in Saudi Arabia scientists finally figured out what the giant creature was: a fungus. (We think.)
The towering fungus spires would have stood out against a landscape scarce of such giants, said New Scientist in 2007.
“A 6-metre fungus would be odd enough in the modern world, but at least we are used to trees quite a bit bigger,” says Boyce. “Plants at that time were a few feet tall, invertebrate animals were small, and there were no terrestrial vertebrates. This fossil would have been all the more striking in such a diminutive landscape.”
Fossils of the organisms, known as Prototaxites, had peppered the paleontological findings of the past century and a half, ever since they were first discovered by a Canadian in 1859. But despite the fossil records, no one could figure out what the heck these giant spires were. The University of Chicago:
For the next 130 years, debate raged. Some scientists called Prototaxites a lichen, others a fungus, and still others clung to the notion that it was some kind of tree. “The problem is that when you look up close at the anatomy, it’s evocative of a lot of different things, but it’s diagnostic of nothing,” says Boyce, an associate professor in geophysical sciences and the Committee on Evolutionary Biology. “And it’s so damn big that when whenever someone says it’ssomething, everyone else’s hackles get up: ‘How could you have a lichen 20 feet tall?’”
That all changed in 2007 when a study came out that concluded the spires were a fungus, like a gigantic early mushroom.
But not everyone was sold on the idea that Prototaxites was an early fungus. No one’s questioning the spires’ existence—people just have trouble trying to imagine that such a huge structure could be a fungus. Researchers trying to refute the fungus idea thought that Prototaxites spires were gigantic mats of liverworts that had somehow rolled up. But in a follow-up study, the scientists who had proposed the fungus idea doubled down on their claim. So science is messy, and despite more than a century of digging, we still don’t really know, for sure, what these huge spires that dominated the ancient Earth really were.
But even though the spire-like mushrooms of yore—or whatever they were—are long gone, don’t feel too bad for funguskind. The largest organism on Earth, says ABC, is still a huge fungal mat, a single organism spread over 2,200 acres of forest in eastern Oregon.
More from Smithsonian.com:
The Sundarbans, an expansive mangrove forest that stretches for nearly 4,000 square miles across India and Bangladesh, is home to the world’s largest population of endangered Bengal tigers. But due to climate change, the Sundarbans are in trouble—and a sobering study published recently in Science of The Total Environment has predicted that by 2070, there will be no viable tiger habitats left in the region.
Situated on the delta of the Ganges, Brahmaputra and Meghna rivers, the Sundarbans supports a wealth of biodiversity in its terrestrial, aquatic and marine ecosystems. But the forest’s location also makes it vulnerable to rising sea levels because, according to the study authors, the mean elevation of most of the Sundarbans is less than one meter above sea level. Previous research has noted other impacts of climate change, like changes in vegetation, salinity and sedimentation in the region.
The new study set out to predict the implications of this shifting environment for the Bengal tiger, the only tiger species that has adapted to living in a mangrove environment. Researchers used computer simulations to analyze scenarios for the years 2050 and 2070, based on climactic trends developed by the Intergovernmental Panel on Climate Change. Their analysis accounted for the effects of both sea level rise and climate change, including factors like extreme weather events. The analysis did not factor in threats like poaching, human-tiger conflicts and disease—but even so, the study authors write, their simulations predicted that climate change and sea level rise alone would be enough to “decimate this iconic species from the Sundarbans.”
One factor affecting tiger habitat is an increase of salinity in the region’s waters, driven by rising sea levels and reduced rainfall, Sharif A. Mukul, lead study author and environmental scientist at Independent University, Bangladesh, told CNN’s Isabelle Gerretsen last month. Higher salt levels are killing the Sundarbans’ Sundri trees, thereby shrinking the tigers’ habitat, and reducing the availability of fresh water. And this is far from the only threat facing the great cats.
“A lot of things might happen,” Mukul tells Kai Schultz and Hari Kumar of the New York Times. “The situation could be even worse if there is a cyclone or if there is some disease outbreak in that area, or if there is a food shortage.”
The Bengal tiger is, of course, not the only animal threatened by changes to its environment. Just this week, a bombshell U.N. report revealed that as many as one million plant and animal species are being pushed towards extinction by human-induced changes to the natural world. And while the situation is dire, for Bengal tigers at least, all hope is not lost. According to Schultz and Kumar, steps are already being taken to mitigate the effects of environmental changes in Bangladesh’s low-lying regions, such as building storm surge walls and redistributing sediment to increase the height of some islands.
Bill Laurance, study co-author and professor at James Cook University in Australia, stresses the importance of conservation measures; establishing new protected areas and cracking down on illegal poaching, he says, would help make the Sundarbans’ ecosystems more resilient in the face of an increasingly erratic climate.
“There is no other place like the Sundarbans left on Earth,” Laurance adds. “We have to look after this iconic ecosystem if we want amazing animals like the Bengal tiger to have a chance of survival.”
By measuring the heat coming from a planet nearly 49 light-years away, astronomers were able to glean some information about the surface of the rocky world—a rare feat in exoplanet science. The observations from NASA’s Spitzer Space Telescope suggest that the exoplanet LHS 3844 b has no atmosphere, and its surface is likely covered in dark volcanic rock, making the planet similar to our moon and Mercury, according to a NASA press release.
The exoplanet, which is a “super-Earth” with about 1.3 times the radius of our planet, was discovered last year by the Transiting Exoplanet Satellite Survey (TESS) space telescope. TESS finds planets via the transit method, observing a slight dip in a star’s light when a planet passes in front from our perspective. Spitzer, an infrared telescope, was then used to take 100 hours of follow-up observations of the exoplanet and its parent star, reports Daniel Clery for Science. Those observations provided evidence that LHS 3844 b lacks an atmosphere, and measurements of the planet’s reflectivity suggest it has a dark surface of possibly basaltic rock. The findings were detailed in a study published earlier this week in Nature.
The exoplanet LHS 3844 b orbits an M dwarf star, also called a red dwarf, estimated to be about 15 percent the mass of our sun. These small and cool stars make up about 70 percent of the stars in the Milky Way, and they can burn for trillions of years—longer than the current age of the universe—making them prime hunting grounds for exoplanets, Adam Mann writes for Scientific American.
Planets around M dwarfs also circle their stars rapidly—LHS 3844 b completes a full orbit in just 11 hours—giving telescopes like TESS ample opportunity to spot them in a transit. However, previous research has questioned whether rocky planets around M dwarfs are likely to hold on to an atmosphere, thought to be a critical feature of habitable worlds.
"We've got lots of theories about how planetary atmospheres fare around M dwarfs, but we haven't been able to study them empirically," said Laura Kreidberg, a researcher at the Harvard—Smithsonian Center for Astrophysics (CfA) and lead author of the new study, in the press release. "Now, with LHS 3844b, we have a terrestrial planet outside our solar system where for the first time we can determine observationally that an atmosphere is not present."
Generally it is difficult for scientists to observe an exoplanet directly because the light reflecting off the planet is drowned out by the much brighter light from the star. However, a few unique conditions allowed researchers to detect light from the surface of LHS 3844 b. With such a close orbit, the planet is almost certainly tidally locked, meaning one side of the planet always faces the star, creating a dayside and a nightside. The star-facing side of LHS 3844 b reaches temperatures of about 1,410 degrees Fahrenheit (770 degrees Celsius), while the nightside stays at about minus 459 degrees Fahrenheit (minus 273 degrees Celsius), as reported by Scientific American.
If LHS 3844 b had a thick atmosphere, the air should transfer heat between the two halves of the planet, equalizing the temperatures a bit. "The temperature contrast on this planet is about as big as it can possibly be," said Kreidberg in the release. "That matches beautifully with our model of a bare rock with no atmosphere."
According to computer simulations, such a contrast in temperatures on LHS 3844 b means that the planet could only have an atmosphere of about one-tenth the pressure on Earth. But in the environment of a red dwarf star, which pumps out high levels of ultraviolet radiation and frequent flares, such a thin atmosphere would almost certainly be blown away, according to NASA.
Given the number of rocky planets discovered orbiting M dwarfs, including the closest exoplanet to us, Proxima Centauri b, astronomers are eagerly working to find out if such worlds could harbor life. The realization that LHS 3844 b likely doesn’t have an atmosphere suggests M dwarfs may be hostile to life after all, but even in such an extreme environment, there may be conditions that could lead to a habitable world.
“For every idea for how to get rid of an atmosphere on a planet, there’s another for how to keep it or make a new one,” Kreidberg tells Scientific American. “I don’t think this counts as a victory point for the naysayers just yet.”