Found 8 Resources containing: Steffen, Will
It’s a joke that if you ask men and women to name colors you’d get basic responses from men (red, yellow, green, blue, dark blue) and some creative ones from women (carnation, lemon, light sage, sky blue, cerulean).
Yet, research has actually borne this joke out to some extent. Women do tend to have a larger, more elaborate color vocabulary.
Israel Abramov, of CUNY’s Brooklyn College, has worked to find out if men and women’s brains are somehow wired differently when it comes to color perception, writes Sadie Steffens for "Lions Talk Science," a blog by Penn State Milton S. Hershey College of Medicine. His work does show differences. Steffens writes:
Abramov asked men and women to break down the hue of a color and to assign a percentage to the categories red, yellow, green, and blue. The results showed that women were more adept at distinguishing between subtle gradations than were men. This sensitivity was most evident in the middle of the color spectrum. With hues that were mainly yellow or green, women were able to distinguish tiny differences between colors that looked identical to men. In fact, Abramov found that slightly longer wavelengths of light were required for men to see the same hues as women – hues identified as orange by women were seen as more yellow by men.
However, when shown light and dark bars flickering on a screen, men were better than women at seeing the bars. Men were better able to perceive changes in brightness across space, a skill useful for reading a letter on an eye chart or recognizing a face. This effect was increased as the bars narrowed, suggesting that men are more sensitive to fine details and rapid movement than women.
Abramov thinks that testosterone might be to blame for this difference. Men have more testosterone receptors than women, particularly in the visual regions of the brain, that might be causing the perceptual differences. Still the exact biological mechanism has yet to be discovered. And men and women aren't the only categories of people who see color differently from each other. So do older people, compared to younger people. And people who work with color—think of artists and designers—have a significantly more enhanced color vocabulary. So the difference between men and women might not be biological, but cultural.
Meanwhile, we will continue to plumb the depths of gender’s effect on color. For example, when Randall Munroe, the creator of the XKCD webcomic, surveyed his readers, he found that A) everyone goes crazy when asked to name colors and B) no one can spell fuchsia. Actually, his full results were even more interesting, so check them out.
On a sunny day this spring Josh Chase, an archaeologist for the Bureau of Land Management, stood on the bluff above Montana’s Milk River and watched as flames raced through one of the most unique archaeological sites on the northern Plains. But instead of worrying about the fate of smoldering teepee rings or stone tools, Chase was excited. He had planned the controlled burn, and even the firefighters on scene could see the fire instantly uncovering a rich record of the bison hunters who lived there 700 to 1,000 years ago.
By burning the 600-acre stretch of grassland in northeastern Montana named after one-time landowner Henry Smith, Chase gained perspective that would have been nearly impossible to achieve with traditional archaeological techniques. A research aircraft later flew over to image the freshly exposed artifacts, including the remains of rock structures used to corral and kill bison, stone vision quest structures where people fasted and prayed and stones arranged in human and animal shapes.
“Before the fire, if we were looking at the site through a door, we were just looking through the peephole,” says Chase. “Now that we’ve burned it and recorded it, we’ve opened the door so we can see everything there.”
As far as Chase knows, it’s the first time an archaeologist has intentionally set a cultural site ablaze. It’s much more common for archaeologists in the Western U.S. to worry about wildfires--or fire-fighting efforts--damaging a site. But since grasslands are adapted to natural fire cycles, Chase had a rare opportunity to use fire as an archaeological tool. It's a tool that has had surprisingly successful results thus far. Chase is still analyzing the flight data from this year’s 400-acre burn, but an initial burn last spring revealed 2,400 new stone features – about one every three to five feet.
When Chase began working on the Henry Smith site in 2010 realized it was going to be too large to map by hand. Plus, vegetation obscured much of it. He knew grass fires to be a natural part of the plains ecosystem, and most of the artifacts there are durable quartzite stones. To Chase, a former wildland firefighter, a controlled burn seemed like a sensible way to expose any artifacts on the surface without harming them.
Since much of the data about fire’s impacts on archaeological sites comes from studying high-intensity forest fires, Chase wanted to be sure that a low-intensity grass fire wouldn’t harm the archaeological record, especially fragile animal bones. So for last year's 300-acre burn, Chase selected a location with only stone artifacts. Within that burn, a crew from the U.S Forest Service's Missoula Fire Science Laboratory fitted mock stone and bone artifacts with heat sensors and burned test plots in different vegetation types. The fire raced over them for only 30 seconds and left the artifacts unscathed. That gave him confidence that this year’s blaze wouldn’t harm the sensitive bison bone fragments in the Henry Smith site.
Archaeologists have known about the existence of a buffalo kill site there since the 1930s. Arrowheads found at Henry Smith identify it as part of the Avonlea Period, when northern Plains bison hunters first started using bows and arrows. But no one studied it systematically until the 1980s, when a researcher identified two spiritually significant stone effigies, and excavated a buffalo jump. To harvest bison, hunting groups built miles-long lines of rock piles, called drivelines. The drivelines helped the hunters herd the running bison towards a rocky bluff where the animals “jumped” into a ravine by tripping and stumbling.
Henry Smith’s overwhelming density of features including vision quest sites, four more effigies and additional drive lines didn’t come into focus until last year’s test burn. This year’s burn revealed stone tools and teepee rings indicating the site was used for day-to-day living in addition to spiritual and hunting purposes. Chase says that it’s very unusual to find all of those features in one location.
While the site is within the traditional territories of multiple American Indian tribes, archaeologists and tribal members have not yet linked it to a specific one, and the area is no longer used by native groups. Chase notififed 64 tribes throughout the U.S. before the burn and had face-to-face meetings with Montana tribes to gather feedback on the burn technique. No one had a problem with it, according to Chase.
This summer, Chase will have more meetings with the region's tribes to get their perspectives on interpreting the site. He'll also be be doing fieldwork to confirm that his is correctly interpreting the aerial images and he’s now developing hypotheses about the Henry Smith site’s significance.
“I would speculate that it probably started as a very good place to get and process bison, and due to that fact it turned into a spiritual place,” he says. “Now we’re looking at that snapshot in time with all those features from all those years of activity laying on top of one another.”
Image by Great Falls Tribune/Rion Sanders. Stones arranged in a circle form a vision quest site, a place where people fasted and prayed. Until a controlled burn swept the area, this site had been hidden by vegetation for hundreds of years. (original image)
Image by Great Falls Tribune/Rion Sanders. Bison teeth found at the foot of a buffalo jump, a site where Native Americans herded bison into a ravine. (original image)
Image by Great Falls Tribune/Rion Sanders. Stone tools are part of the features at an archeological site near Malta, in northeastern Montana. (original image)
Fire has also influenced how Larry Todd, an emeritus anthropology professor at the Colorado State University, interpreted the archaeology of Wyoming’s wilderness. Instead of excavating deep into a small area, he surveys the surface for artifacts that provide a big-picture view while making minimal impact on the land. Todd had spent five years been mapping a site in the Absaroka Mountains just southeast of Yellowstone National Park when the Little Venus wildfire burned through in 2006. In the aftermath, he realized that he had been studying a severely watered down version of the archaeological record.
The fire increased the artifacts visible on the surface by 1,600 percent. The vegetation had also hid high-quality artifacts. There were many more bone fragments, fire pits, trade beads and ceramic figurines – the kinds of objects that contain a lot of information for archaeologists.
That changed Todd’s interpretation of the site. He now thinks that Native Americans used Wyoming’s mountains much more intensively and for more of the year than his earlier work showed. “The most amazing thing that the fire has exposed is our ignorance,” he says.
For Todd though, the increased knowledge comes with a cost. Fires expose artifacts to looting, erosion, weathering, and the hooves of free-ranging cattle that “take that beautiful crisp picture of what life was like in the past and make it look like it went through a Cuisinart.”
It pains Todd that he can’t get to every site in time. “When a fire burns through an area, and they are literally some of the most spectacular archeological sites you have ever seen, it’s a real mix of emotion,” he says. “You’re sort of saying, ‘Oh my God this is going be gone, and I don’t have the time, and I don’t have the people, and I don’t have the funding to record it properly.’ It’s thrilling, but depressing at the same time.”
Chase avoided those tradeoffs at Henry Smith because many of its artifacts aren’t fire-sensitive, the site is protected from looters by the private ranches surrounding it, and he had the luxury of planning for a controlled burn. His work will be important to understanding not only the people who lived and hunted there, but also how to protect and study grassland cultural sites after future wildfires or prescribed burns.For a test burn in 2015, BLM architects placed temperature sensors within mock cultural sites. (Bureau of Land Management)
Ana Steffen, an archaeologist working at New Mexico’s Valles Caldera National Preserve, has seen some of the worst of what fire can do. In 2011, the Las Conchas fire burned 156,000 acres in the Jemez Mountains and set a new record for the state’s largest fire at the time. The fast-moving conflagration spread at the rate of about two football fields per second, denuding much of the forest.
“What we realized was Las Conchas the worst-case scenario by every measure for archaeology,” says Steffen. “Not only did it burn a huge area, it burned large areas really, really badly with severe direct effects, and with terrible indirect effects later on.”
In the end, the Las Conchas fire affected more than 2,500 archaeological sites. After withstanding centuries of more moderate fires, Ancestral Puebloan dwellings crumbled, pottery disintegrated, and flint and obsidian artifacts shattered. Then flash floods ripped through the bare soils, carrying away 25-acre obsidian quarries used by Archaic period hunter-gatherers.
Steffen is now part of a team trying to make the most out of the Las Conchas fire. Researchers are doing controlled lab experiments to model how archaeological materials respond to a variety of fire conditions. That will help archaeologists and fire managers figure out when it’s safe to do prescribed burns, and how to protect features from wildfire. It will also help archaeologists understand past fire severity when they are looking at a site.
A history of suppressing low-intensity wildfires helped contributed to the Las Conchas fire’s severity, so Steffen applauds using prescribed fire as an archaeological tool. “Being able to return fire to the landscape is a wonderful way of humans interacting with the environment,” she says. “I find it to be very, very healthy. So mobilizing a case study such as this one where you can get archaeologists out on the landscape, where you can see what’s happening after the fire, that’s just smart science.”
There's still a lot to learn by studying how fires affect cultural sites, and researchers have ample opportunity to do that work. For example, on the Shoshone National Forest where Todd works, fires have been getting larger and more frequent over the last 20 years. During one field season the ashes of an active wildfire fell on him as he examined the aftermath of an old one. “There’s a whole suite of really complex interactions going on that are probably going make fire archaeology something we’re going to see more of in the future,” he says.
Walking along the edge of a seasonally dry lakebed on the eastern outskirts of Mexico City, there is near perfect silence except for the occasional airplane that flies overhead.
These planes flying out of a nearby airport are a reminder of the estimated US$13 billion international airport that had been planned and partially constructed on top of the seasonal wetlands native to this place. Then, in 2018, Mexico’s new president, Andrés Manuel López Obrador, canceled the project and moved forward with plans to construct what would be one of the world’s largest urban parks instead. Experts from around the world hope the project, if successful, will serve as an example to other cities of what is possible in the fight against climate change.
Turning Back the Clock
The size of the proposed park is nearly unfathomable from ground level, covering 12,300 hectares (30,394 acres) and stretching 16 kilometers (10 miles) from end to end. That’s about the size of 36 New York Central Parks or more than twice the size of Manhattan.
The government and the architect behind the park, known as Parque Ecológico Lago de Texcoco, see great potential in the park — particularly in the face of mounting water shortages, floods and climate change. They view this mega project as one that could turn back the clock on disruptions to the region’s water systems dating back to Hernán Cortés and the Spanish siege of Tenochtitlan in 1521.
The region’s lakes were the primary source of freshwater during Aztec times, but the Spanish drained the valley’s lakes after they took over the city of Tenochtitlan. This forced an independent Mexico centuries later to construct hundreds of miles of pipes to bring in roughly 30 percent of the city’s water and to pump the rest from an underground aquifer. The city is now pumping water out of that aquifer twice as fast as water is returning via rainfall.
On the other side of the equation, the city, which has been largely paved over, floods for months during the rainy season.
“The problem is we cannot turn 500 years of history and go 180 degrees overnight,” says Mexico City architect Iñaki Echeverría, executive director of the park project. “Very few times you are offered the possibility that can have an impact that can really change things. If we manage to do this, it changes the direction of the history of the city and the valley.”
The project is designed to be constructed in the basin of the former Lake Texcoco, which dried as Mexico City expanded into a megacity of more than 20 million people over the past two millennia. The area has not been inhabited and has been off-limits to the public due to annual flooding and infrastructure issues.
Echeverría is seeking to restore the vast majority of the area to its former state, including rejuvenating numerous lakes that were drained, as well as wetland areas. One of the goals of the project is to merge the concepts of public spaces and green infrastructure, providing hiking trails, sports courts and lakes for recreation, while bringing back the lakes to rebalance the Valley of Mexico’s water system. That includes routing stormwater runoff into the wetlands and replenishing aquifers.
“This is really the only space that’s left [in the city] and it’s federal land and it’s untapped,” Echeverría says. “It was going to disappear. Right now there’s a possibility to keep it, so we are really working hard to make this happen as soon as possible, to bring people here to understand that this is not a fantasy. This is something that can happen.”
The government hopes to open up the first section of the park project by 2021, according to Echeverría. The architect, who grew up in Mexico City, says he is feeling the pressure from all angles to complete the project or get each component on the right path before the end of the current presidential administration in 2024.
“People are expecting me to fail. A lot of people. For the right reasons, for the wrong reasons, for every reason,” Echevarría says. “There’s a lot of people betting this will not happen, so of course there’s pressure.”
Lessons for Other Cities
In addition to the water-system goals of the park, the project team is planning for a significant solar power component and is considering wind and biofuels to offset maintenance costs.
“I cannot afford the luxury of just going crazy on the beauty of this place like I used to,” Echeverría says, referring to his previous work designing projects; now, as the director of the entire project, he has to worry about more than just design, such as costs and implementation. “I have to give it the means to maintain itself,” he says. “The means to grow, the means for it not to disappear after this government is gone.”
Echeverría had proposed a design for the park 10 years ago, but that plan was quashed to make way for the airport project.
“We thought it was dead for sure and it suddenly comes back to life again. I’m not mystical or anything, but it’s almost like the lake is refusing to die completely,” Echeverría says. “It’s fighting. I think we had to get involved in that fight.”
The government’s decision to dedicate an enormous plot of land for natural area and green infrastructure so near the city center is a progressive one that experts say could affect the future of public spaces around the world.
“If this is successful, a lot of people will go there and learn from it,” says Steffen Lehmann, director of the University of Nevada, Las Vegas, School of Architecture and co-director of the interdisciplinary Urban Futures Lab. “Cities are learning from each other. Cities are learning that they should share their best practices.”
Lehmann, an internationally recognized architect and author on sustainable architecture and urban design, pointed to New York’s High Line project and the “High Line-ization” of copycat parks around the world as an example.
“It’s going to have a huge impact,” Lehmann says of the upcoming Mexico City project. “We need urban forests with climate change, and we need those parks to keep cities cool because of the urban island effect. Cities heat up and store and trap solar radiation and store heat like an oven. It’s underestimated. It’s a big silent killer.”
The project will also capture carbon and mitigate air pollution.
Lehmann says there is an ongoing struggle against the privatization and urbanization of public space in cities around the world.
“This is the kind of work that cities are hungry for. They are looking for ways to include good local governance practices and good water management practices,” says Raul Pacheco-Vega, a water scholar at Centro de Investigación y Docencia Económicas, a Mexico City-based think tank. “Here you kill three birds with one stone. You improve urban governance by providing more green space, you improve water management, and you showcase measures of adaptation to climate change.”
Setting a Precedent
Echevarría is directing the project for the National Water Commission (Conagua), and has gathered a diverse team of ecologists, architects, planners, landscapers, biologists and politicians to bring the project to life.
The first phase, restoring Lake Nabor Carrillo and building public sporting facilities in a portion adjacent to it, is expected to break ground in early 2020. That portion will also include a 10-kilometer (6-mile) running trail around the lake.
Eventually, the project will expand to the area where the airport had been partially built and involve restoring the Casa Colorada lake, which will flood the already-built runway and terminal foundations.
“There’s a lot of things that have to happen over there,” Echevarría says, referring to an ongoing legal battle over the canceled airport. “I’ve tried to keep a very cold mind about that. We have so much work to do without even touching that area. We will work on that. From a project stance, we will begin working as soon as it’s legally permitted.”
The project is located roughly 10 miles (16 kilometers) from the city’s Centro Histórico and is directly adjacent to some of the poorest neighborhoods in Mexico City, according to Echevarría.
“It would be something of a life-changing situation if this space could be created and be next to what is the highest rate of crime and highest rate of poverty in the entire metropolitan region,” he says.
The project currently is being funded completely by public money, according to Echevarría; but he says his team is looking into private funders for portions of the site, including the renewable energy production areas.
Preliminary studies required for the project were estimated at US$11.78 million, according to Conagua.
This piece was originally published on Ensia, a nonprofit media outlet published by the Institute on the Environment at the University of Minnesota.
When more than 100,000 endangered saiga antelopes mysteriously died on the grasslands of Central Asia this spring, experts were baffled. Now they are getting closer to finding out why so many animals died.
The saiga succumbed to something that left their corpses with swollen bellies and blood in their noses and mouths, reports Dinara Urazova for Tengrinnews. Suspecting some kind of infectious agent, a group of specialists led by Steffen Zuther, the acting director of the Association for the Conservation of Biodiversity of Kazakhstan, tramped out onto the steppe and sampled grass, water and soil to find the culprit.
Preliminary results indicate that the saiga were killed by hemorrhagic septicemia, an infection caused by bacteria that rapidly multiply and produce toxins. "The researchers suspect that the pathogens were spread by ticks that populate the steppes in great numbers in late April [and] early May," Urazova writes.
More than 134,000 animals died in two weeks — nearly one-third of the worldwide population. And the recent scourge wasn't the first time the endangered antelopes have died in large numbers. In fact, saigas are known to be prone to mysterious massive die-offs, reports Henry Nicholls for Nature. He writes:
These usually occur when the females come together to calve in the spring. In 1984, such an event in the Ural Mountains resulted in the loss of 100,000 animals — 67% of the local population. There were several smaller-scale die-offs in the 2000s. But this year’s mass-death event among animals living in the Betpak-Dala region of Kazakhstan is much more significant as entire herds are dying.
The experts also preformed necropsies — animal autopsies — to see if they could find the cause of death. While the nature of the infection has been agreed upon, the experts still haven’t concluded which bacteria is responsible. Richard Kock, a wildlife veterinarian at the Royal Veterinary College in the U.K. told Nature in May that multiple types of bacteria could be acting in concert.
Tengrinnews reports that test results will be ready by the beginning of September. Once the mystery of the saiga die-off is solved, experts will turn their attention to another quandary — how to prevent mass deaths in the future.
Name: Natalie Golda
Location: Long Beach, California
Games and Medals: Athens 2004 (Bronze); Beijing 2008 (Silver)
Key Quote: “The game always presents different scenarios and you have to read each situation as it comes. I also love the physicality. You have to be smart, but you have to be fit and tough as well.”
Favorite Olympic Moment: “Walking in the Opening Ceremonies and standing on the medals podium are memories and feelings I will never forget.”
Cap - the funny hat players wear. The cap protects a player’s ears from any kind of impact (fist, elbow, foot), dictates what team you are on (light or dark), and shows your number for the referees.
Tank/Course - our field of play (the pool)
Goal – At either end of the tank is a goal, 3 meters wide and 0.9 meters tall, floating on the water.
Ball – The ball weighs 400 grams to 450 grams. The circumference of the ball used in women’s games is slightly smaller than the one used by men.
1. Weak - When a player is open on the opposite side of the pool, you yell “weak” to get the attention of the player with the ball and make them pass it to the open player.
2. Hockey Sub - You can substitute during play if the player that needs to come out swims to the penalty box; the new player can then swim into the field of play.
3. Donut/Bunny - When the shooter shoots the ball in between the goalie’s arms directly over the goalie’s head.
Turn - On offense, you may “turn” a defender either by using her momentum against her or by using your off-arm to hold and spin to gain an inside water advantage.
Stunt/Gap - On defense, if you wanted to slow down an attacking offensive player on the counter-attack, you may “stunt” or “gap.” It is a fake out; you pretend like you are going to go at the offensive player. The motion stops that player from moving forward and allows your teammates time to close in to help.
Fouls - One whistle is an ordinary foul. Ordinary fouls, usually made by the defense, are not added up and counted against you like in basketball. Two whistles indicate an offensive foul, meaning the offensive player did something illegal to gain an unfair offensive advantage. The ball immediately turns over to the defense. Three whistles means there has been an exclusion/ejection. Similar to hockey, the offending player has to sit in the ejection box for 20 seconds, and the offensive team gets a 6x5 advantage.
In basketball, a player holding the ball can get fouled; in water polo, the offensive player must let go of the ball in order to draw a foul. While the player is holding the ball, the defense can do almost anything short of dunking or punching a player, but once the offensive player releases the ball, the defense must let go and get off of the offensive player in order to avoid a foul being called.
Defenders sometimes sink or hold back an opponent, especially to take away a scoring opportunity, but this warrants a major foul. Three major fouls per game (20 seconds in the penalty box each time) and you are out.
2004 - In Athens, the women had to play on a 30-meter-long course, which is usually reserved for men. For 2008, the women’s course was switched back to its traditional 25 meters. It has been kept at 25 meters for 2012 as well.
2005 - In most sports, whoever touches the ball last before it goes out of bounds stays on defense, and the offensive team retains possession. However, in water polo, thanks to a rule change in 2005, if the field player (any defensive player other than the goalie) tips the ball out of play on a deflected shot or pass, that defensive team takes over possession. If the goalie tips the ball out of play, the offense retains possession.
2008 - Prior to the 2008 Olympics, when an offensive player was fouled, she would always have to “get live” by passing the ball to a teammate and getting it back before she took a shot on goal. Now, if she is outside the 5-meter marker, she may shoot the ball directly after she is fouled, but it must be in one fluid motion with no fakes or hesitation.
This team won the qualification tournament in Italy, knocking the defending Olympic champions (Holland) and the reigning World Champions (Greece) out all together. I’m excited to see what they can do.
Maggie, who graduated high school just last year, plays with such confidence and swagger. I love watching her step up to the most experienced in the world and win 1x1 battles. @maggiesteffens
One of the more memorable players you will see in these games, Casanova has the body of a giant and amazing hands. She doesn’t look very athletic, but this woman can move.
Photos by USOC/Long Photography; AP Photo/Steve Holland; Wikimedia Commons
Waiting in line for their weigh-in, the lumpy, pale pumpkins sag on their pallets like deflated balloons. But to become a world heavyweight champion, looks don’t really matter. When it comes to this competition, decades of intense selective breeding have banished the petite, perfectly ovoid and brilliantly orange fruits with a focus on one exclusive trait: massive size.
Every year, an international community of giant-pumpkin farmers loads up beastly gourds on trailers, carting them to local fairs and weigh-ins for a chance at the title.
The size of these pumpkins is unimaginably large to me—I can barely grow tomatoes without making heart-breaking tears through their delicate flesh, innards dripping to the ground. So I went to scientists and competitive pumpkin growers to ask this burning question: How do you make a monster pumpkin?
The current world record is held by Beni Meier, a Swiss accountant by day, who grew a pumpkin that weighs in at 2,323.7 pounds, roughly the same amount as a small car. But it’s likely he won’t hold that title long. These giants have been growing in mass by leaps and bounds every year, and there are no signs that they’re slowing down.
“The weight is still continuing to go up ... 1,000 pounds was the goal 15 years ago, and everyone thought that was unheard of,” says Woody Lancaster, a competitive pumpkin grower and so-called heavy hitter, or someone who consistently churns out monsters. His 1,954-pounder ranked 14th in the world this year.
According to Lancaster and other growers, there are a few basic tenants to cultivating giant pumpkins: Keep them at the perfect temperature, give them continuous food and water, protect their delicate skins from drying and cracking and cover them at night for warmth. Competitive growers also lovingly prune their pumpkin plants, reducing their fruit to a few prized gems. But above all, you have to start with a champion seed.
George Hamilton, extension field specialist in fruits and vegetables at the University of New Hampshire, ranks the relative importance of a grower's checklist something like this: “Number one is genetics, number two is genetics, number three is genetics. And then number four you’ve got sun, warmth, fertilizer and water,” he says.
These days, nearly every prizewinning pumpkin can trace its roots back to Howard Dill’s Atlantic Giant. Dill spent 30 careful years cultivating his beasts from the Mammoth pumpkin varieties, which are rooted in the squash species Cucurbita maxima.
In 1981, Dill scored a world record with a 493.5-pound beast, trampling the previous record of 460 pounds. He patented the seeds, and an international cohort of growers continued to selectively breed them for bigger pumpkins.
Just under 35 years later, the weight record for the pumpkins has more than quadrupled.
"Basically it's like horse racing. We’re breeding big pumpkins into big pumpkins every year to create bigger pumpkins," says Ron Wallace, another heavy hitter who holds multiple growing titles. Last week, Wallace broke the North American weight record with his 2,230-pound behemoth.Ron Wallace poses with his record-setting 2,230 pound monster. He now holds the record for heaviest pumpkin in North America. (Courtesy of Ron Wallace)
So why can these monsters grow so large? Atlantic Giant pumpkins can pack on close to 50 pounds a day during peak growing season, says plant physiologist Jessica Savage at the Arnold Arboretum at Harvard University. Though a pumpkin is roughly 90 percent water, there is still a great deal of sugar flowing into the plant’s bulk.
Oddly enough, the giant plants aren’t any better at producing sugar than their regular-sized cousins, explains Savage. They’re just better at moving it around.
To take you back to high school biology, plants have two types of tissue that work to get food and water flowing through them: xylem and phloem. The xylem transports water into the plants, and the phloem is responsible for sugar movement. While all pumpkins easily move large amounts of water, Savage found that giant pumpkins have supersized phloem.
Growers have also harnessed the power of mycorrhizal fungi, which happily colonize the plant’s roots and assist water and nutrients flowing into the plant in exchange for carbohydrates, explains Wallace, who originally introduced the fungi to extreme gardeners. With increasing demand for his special fungi-containing elixirs, Wallace started selling the mixes this past February, and business is booming.
So is there a biological factor that will eventually limit their size?
Not really. These monsters are so good at moving sugars, that given the proper conditions, there isn't anything glaring that limits their growth, says Savage. "It seems like everything in the plant just increased with the fruit size."
Another grower, Matt DeBacco, suggests that the limit may be in the cells. Plants get large in two stages. First they divide and multiply their cells, then the cells begin expanding. Each individual cell can expand up to a thousand times its original size, so if the pumpkin has more cells to start with, it can expand much faster in the late season, when growth often becomes sluggish, DeBacco explains.
DeBacco, dubbed “mad scientist Matt” by his local community, is currently tinkering with a brew of hormones and amino acids to prolong the initial period of cell growth. Already his method has produced gourds estimated to weigh over 2,000 pounds, and he thinks there may still be room for some tinkering.
“I think that is the last thing that we try before we actually sequence them and change the G’s, the A’s, the T’s and the C’s,” says DeBacco, referring to the chemical base pairs that make up DNA.
In the end, the limit may come down to physics. Giant pumpkins already sag under their own weight, developing heart-wrenching cracks if they grow too quickly or unevenly. But the sagging may actually be one of the keys to continued growth, according to researched published in the International Journal of Non-Linear Mechanics.
Lead author David Hu and his team used vices to test how much force some ill-fated pumpkins could withstand. They discovered that round pumpkins could put up with a lot. Based on these tests, they estimated that a perfectly uniform pumpkin could grow up to a whopping 20,000 pounds. As the pumpkins flatten, things get more complicated, but flattening does seem to help the gourds hold up their massive bulk without cracking.
So although we might not ever have pumpkins big enough to serve as chariots, we already have some large enough for boat rides, and maybe they’ll keep expanding horizontally. The extreme gardeners will just have to go on growing their massive gourds to find out.
Image by © Daniel Bockwoldt/dpa/Corbis. Two people help guide a monster squash onto a scale during the 2013 European championship in Ludwigsburg, Germany, (original image)
Image by © Zou Zheng/Xinhua Press/Corbis. Spectators gather around the giant pumpkins on display at one of the largest indoor agricultural shows in the world in Toronto, Canada. (original image)
Image by © Patrick Pleul/dpa/Corbis. Pumpkin grower Oliver Langheim poses with his portly pumpkin. A tiny Baby-Boo pumpkin sits on top, looking even tinier compared to the Atlantic Giant. (original image)
Image by © SEBASTIAN KAHNERT/epa/Corbis. If you are currently asking what one does with such a giant pumpkin, here's one option: hollow it out into a boat. This image is from the 2014 pumpkin regatta in Ludwigsburg, Germany. (original image)
Image by © Peter Steffen/dpa/Corbis. The pumpkins require a special rigging of straps to ensure their safety during movement from the fields to the scale, as pictured here at this year's pumpkin growing championship in Boerssum, Germany. (original image)
Image by © Thomas Kienzle/dpa/Corbis. Swiss gardener Beni Meier, poses next to his prized gourd. This pumpkin currently holds the world record at 2323.7 pounds. (original image)
Image by © PATRICK PLEUL/epa/Corbis. Through the years of selective breeding, many of the Atlantic Giants have lost their brilliant orange glow. But it still hangs on in some strains, like the one pictured here with hobby gardener Silvia Manteuffel. (original image)
According to the textbooks, all humans living today descended from a population that lived in east Africa around 200,000 years ago. This is based on reliable evidence, including genetic analyses of people from around the globe and fossil finds from Ethiopia of human-like skeletal remains from 195,000–165,000 years ago.
Now a large scientific team that I was part of has discovered new fossil bones and stone tools that challenge this view. The new studies, published in Nature, push back the origins of our species by 100,000 years and suggest that early humans likely spanned across most of the African continent at the time.(Jean-Jacques Hublin, MPI-EVA, Leipzig)
Across the globe and throughout history, humans have been interested in understanding their origins—both biological and cultural. Archaeological excavations and the artefacts they recover shed light on complex behaviours—such as tool making, symbolically burying the dead or making art. When it comes to understanding our biological origins, there are two primary sources of evidence: fossil bones and teeth. More recently, ancient genetic material such as DNA is also offering important insights.
The findings come from the Moroccan site of Jebel Irhoud, which has been well known since the 1960s for its human fossils and sophisticated stone tools. However, the interpretation of the Irhoud fossils has long been complicated by persistent uncertainties surrounding their geological age. In 2004, evolutionary anthropologists Jean-Jacques Hublin and Abdelouahed Ben-Ncer began a new excavation project there. They recovered stone tools and new Homo sapiens fossils from at least five individuals—primarily pieces of skull, jaw, teeth and some limb bones.
To provide a precise date for these finds, geochronologists on the team used a thermoluminescence dating method on the stone tools found at the site. When ancient tools are buried, radiation begins to accumulate from the surrounding sediments. Whey they are heated, this radiation is removed. We can therefore measure accumulated radiation to determine how long ago the tools were buried. This analysis indicated that the tools were about 315,000 years old, give or take 34,000 years.
Researchers also applied electron spin resonance dating, which is a similar technique but in this case the measurements are made on teeth. Using data on the radiation dose, the age of one tooth in one of the human jaws was estimated to be 286,000 years old, with a margin of error of 32,000 years. Taken together, these methods indicate that Homo Sapiens—modern humans—lived in the far northwestern corner of the African continent much earlier than previously known.Some of the Middle Stone Age stone tools from Jebel Irhoud (Morocco) (Mohammed Kamal, MPI EVA Leipzig)
But how can one be sure that these fossils belonged to a member of our species rather than some older ancestor? To address this question, the anatomists on the team used high-resolution computed tomography (CAT scans) to produce detailed digital copies of the precious and fragile fossils.
They then used virtual techniques to reconstruct the face, brain case and lower jaw of this group—and applied sophisticated measurement techniques to determine that these fossils possessed modern human-like facial morphology. In this way, they could be distinguished from all other fossil human species known to be in Africa at the time.
The high-resolution scans were also used to analyse hidden structures within the tooth crowns, as well as the size and shape of the tooth roots hidden within the jaws. These analyses, which were the focus of my contribution, revealed a number of dental characteristics that are similar to other early fossil modern humans.
And although more primitive than the teeth of modern humans today, they are indeed clearly different from, for example, Homo heidelbergensis and Homo neanderthalensis. The discovery and scientific analyses confirm the importance of Jebel Irhoud as the oldest site documenting an early stage of the origin of our species.
As a palaeoanthropologist who focuses on the study of fossil bones and teeth, I am often asked why we don’t simply address these questions of human origins using genetic analyses. There are two main reasons for this. Although incredibly exciting advances have been made in the recovery and analysis of genetic material from fossils that are several hundreds of thousands of years old, it seems that this is only likely to be possible under particular (and unfortunately rare) conditions of burial and fossilisation, such as a low and stable temperature.
That means there are fossils we may never be able to get genetic data from and we must rely on analyses of their morphology, as we do for other very interesting questions related to the earliest periods of human evolutionary history.The fossils as they were found (Steffen Schatz, MPI EVA Leipzig)
Also, understanding the genetic basis of our anatomy only tells us a small part of what it means to be human. Understanding, for example, how behaviour during our lives can alter the external and internal structure of hand bones can help reveal how we used our hands to make tools. Similarly, measuring the chemical composition and the cellular structure of our teeth can tell us what we were eating and our rate of development during childhood. It is these types of factors that help us really understand in what ways you and I are both similar and different to the first members of our species.
And of course, we should not forget that it is the archaeological record that is identifying when we started to make art, adorn our bodies with jewellery, make sophisticated tools and access a diverse range of plant and animal resources. There have been some intriguing suggestions that human species even older than Homo sapiens may have displayed some of these amazing behaviours.
More such research will reveal how unique we actually are in the evolutionary history of our lineage. So let’s encourage a new generation of young scientists to go in search of new fossils and archaeological discoveries that will finally help us crack the puzzle of human evolution once and for all.