Found 3,005 Resources containing: Environmental Change
Based on decades of cutting-edge research, the 15,000-square-foot Hall of Human Origins offers visitors an immersive, interactive journey through 6 million years of human evolution spelling out how defining characteristics of the human species have evolved during millions of years in response to a changing world.
The post New Hall of Human Origins points to environmental change as major force in evolution of hominins appeared first on Smithsonian Insider.
Environmental change prior to the K-T boundary inferred from temporal variation in the morphology of cheilostome bryozoans
Conservatism of Late Pennsylvanian vegetational patterns during short-term cyclic and long-term directional environmental change, western equatorial Pangea
Environmental groups have often used charismatic megafauna in campaigns to increase public awareness about conservation efforts. By employing people’s inherent interest in these animals, they are able to attract attention towards needs which might otherwise have been disregarded. For example the polar bear has been used to highlight issues ranging from wilderness preservation to climate change.
More than a half century after it hit shelves, the humble Lego brick remains a wildly successful toy, thanks to the building block’s versatility as well as multiple licensing deals over the last decade (which, most recently, catapulted the company over Mattel to make it the top toy maker in the world).
But Lego bricks have also occasionally found their way into laboratories as tools for scientific research. A team at The University of Cambridge, for instance, used the bricks to build synthetic bones.
Now, researchers at Iowa State University have turned to transparent Lego bricks as a novel, low-cost way to study plant growth. The work, recently published in the journal PLOS One, argues that the bricks can be used to create highly precise, centimeter-scale systems with chemical gradients to study how chemical changes affect root growth.
Understanding how chemical and environmental changes affect plant root growth could increase crop yields and give us a better understanding of how certain crops will react to climate change.
Ludovico Cademartiri, an assistant professor of materials science and engineering at Iowa State University and a co-author of the paper, told Smithsonian.com that the idea of using Legos came out of a brainstorming session sparked by how surprisingly little is known about the way plants respond to environmental changes.
“There is a growing consensus that it is one of the most important areas that needs development for plant science and Agronomy,” Cademartiri says. “If we want to improve our crop yields, we need to learn how plants respond to very complex environmental cues.”
He says the reason we don’t yet know more about the subject is, in part, because of a lack of tools available for these precise kinds of experiments. High-level techniques have long existed to study small single- or multi-celled organisms, but plants present a problem in that they start out tiny and grow much larger throughout the time of study. Greenhouses work well for large studies that require all plants to have a homogeneous external environment (the same level of heat and humidity, for instance, among other factors). But imagine a plant experiment in which scientists might need to set up 100 plants in 100 different controlled environments, both above and below the soil level, with each setup allowing enough room for the plant to grow, and you start to get a sense of the problem.
Existing microfluidic technologies allow scientists like molecular biologists to control test environments with the precision of a millionth of a meter, but those systems can be very difficult and expensive to scale up for plant research.
Transparent Lego bricks present a happy medium, in that they are affordable but create environments precise enough for serious study, as Cademartiri and his team learned when they began to investigate the idea.
The researchers chose off-the-shelf transparent Lego pieces, which can be purchased individually directly from Lego's Website, put them in an autoclave for sterilization, then used the pieces to build rectangular containers to hold the gel or other soil substitute. The containers can be built to varying sizes to accommodate different plant sizes or root types. When an experiment is over, the pieces can be broken down, cleaned and used again.
Doctoral student Kara Lind, another author of the study, worked on ways to ensure Lego bricks could hold the transparent gels that are used as soil substitutes to allow researchers to easily see root changes, the Iowa State News Service reported. She also worked out ways to create specific chemical gradients within the structures, to see how plants react to different chemicals, be they toxins or nutrients.
The result: “It turned out that Lego performed a lot better than we thought, for a couple of reasons,” Cademartiri says.
For one, a “transparent Lego is made of polycarbonate, so that means it can be sterilized, which makes it ideally suitable for biological work," he says. The bricks are also chemically inert, so they won’t react with surrounding materials and potentially spoil experiments.
The team aims to continue to develop Legos as a platform and tool set for serious plant study, in the hopes that other scientist will find the iconic bricks useful in their own research.
Cademartiri says it’s too soon to tell to what extent scientists will or won’t take up Legos for plant study, but he is optimistic. Educators have long been using Legos in classrooms, and the company's Mindstorms robotics line, aside from being used to help build artificial bones, have also been used by researchers at the University of Vermont to create robots that change their shape to "learn" how to walk. So it's at least likely that Lego bricks will continue to find an occasional home in research laboratories as well as the toy box.
“What we did was to force ourselves to create the simplest, cheapest, most convenient, and capable tools that we could devise,” Cademartiri says. “So, we’re hoping that other scientists will find them useful, and we think they will.”
Is climate change a matter of national security? In a warming world, sea-level rise, drought and soil degradation are putting basic human needs such as food and shelter at risk. In March, the U.S. Department of Defense called climate change a "threat multiplier," saying that competition for resources "will aggravate stressors abroad such as poverty, environmental degradation, political instability and social tensions—conditions that can enable terrorist activity and other forms of violence."
Connecting climate change to a global increase in violence is tricky, and attempts to make such a link receive a fair amount of criticism. A hotter planet doesn't automatically become a more conflict-ridden one. The 2000s, for instance, saw some of the highest global temperatures in recorded history—and some of the lowest rates of civil conflict since the 1970s.
But there are historical examples of civilizations that did not fare well when faced with drastic environmental change, and those examples may offer a window into the future—and even help prevent catastrophe. "We can never know with 100-percent certainty that the climate was the decisive factor [in a conflict]," says Solomon Hsiang, assistant professor of public policy at the University of California, Berkeley. "But there's a lot of cases where things look pretty conspicuous."
Doing environmental research isn't easy. From wild animals to foul weather, researchers have to jump lots of unexpected hurdles while collecting data. But as The Guardian’s Ashifa Kassam reports, for one group of Canadian climate scientists, the obstacle standing in their way was their research subject itself: climate change.
A huge study called BAYSYS launched earlier this year with the goal of understanding how climate change affects the Hudson Bay. BAYSYS is a massive undertaking. The project is composed of five research teams of scientists from seven Canadian universities and Manitoba Hydro, and costs over $11 million U.S. dollars. But in May, the first leg of the trip went horribly wrong and scientists were forced to turn back.
Blame a bevy of icebergs for the abandoned trip. As Kassam reports, an icebreaker the researchers were using got diverted off the coast of Newfoundland when huge chunks of ice trapped boats in the area. When the team studied the ice that was holding up their boat, notes Kassam, they realized it was Arctic ice that had made its way south due to—you guessed it—climate change.
The Canadian Coast Guard tells CBC News’ Laura Glowacki that they had never seen those kinds of conditions in the area. Glowacki reports that the ice was multi-year ice, not the thinner varieties that can be found on the North American coast. It usually forms in the Arctic due to the landlocked geography of the region. But because it forms over many years instead of a single season, explains the National Snow & Ice Data Center, it’s much tougher than other ice and can be hard for icebreakers like the one used by the Canadian scientists to sail around and clear away.
According to NASA, over 13 percent of all Arctic sea ice is melting every decade. This ice melt serves as a kind of bellwether of the severity and pace of climate change. The melt is driven by a warming atmosphere, which in turn heats the oceans. As warmer water circulates, multiyear ice thins. Chunks of this ice break off and are carried along on the ocean’s currents. Thinning also reduces the insulating properties of the ice, which protects the freezing arctic atmosphere from the relatively warm ocean waters. But without this barrier, the atmosphere has no insulation from the ocean heat, further warming the planet.
In the future, that melt could do much more than cut scientific missions short. As ocean physicist Peter Wadhams notes for Yale Environment 360, scientists expect a barrage of cascading effects from Arctic ice melt. The Arctic ice that does remain is expected to absorb less heat, warming global temperatures. As permafrost melts, it spews warming methane in to the atmosphere. And all that escaping water means more atmospheric water vapor, which in turn warms the air even more.
As for the expedition, all is not lost. Kassam reports that its second leg will continue in July. If anything, it shows how important climate change research will be as long as scientists can make it to the areas they need to explore to learn more.