Study: Monarch Caterpillars Get Angry When They’re Hungry
Humans aren't the only animals that get "hangry" when deprived of a meal.
"The less food that is present, the higher their level of aggression," study coauthor Elizabeth Brown of Florida Atlantic University told New Scientist.
The idea for the study was born when the wife of fellow Florida Atlantic University researcher Alex Keene saw two monarch caterpillars fighting over a milkweed plant in the couple's garden, The New York Times reported.
"I decided to investigate monarch caterpillars because I was intrigued by their combative behavior, which I observed first-hand in my own garden," Keene explained in a Florida Atlantic University press release. "They are large and easily recognizable compared to many other insects. These are charismatic animals that everyone loves, and there's a growing appreciation for their potential to tell us about how the brain controls behavior."
The researchers gave the caterpillars three different amounts of food, New Scientist reported. The less milkweed the caterpillars received, the more aggressive they became. The caterpillars who were larger and closer to metamorphosis were the most aggressive, probably because they required more energy, Brown said.
Caterpillar aggression looked like a "combination of boxing and 'bumper' cars," the press release detailed, with caterpillars head butting or knocking other caterpillars away from the food.
"I went to grad school with a guy who played rugby in college," Keene told The New York Times. "A flying head butt is a fair assessment."
The attacked caterpillar would then shuffle away from the food, defeated. This is a big problem for the losing caterpillar, since monarch caterpillars essentially eat non-stop from hatching to forming a cocoon.
The researchers hope to build on this study to learn more about the genetic drivers of aggressive behavior.
"There's a lot we could learn about more complex animals from this ecologically relevant insect model," Keene told New Scientist.
The research could also have conservation implications. Monarch caterpillars mainly dine on milkweed: They can strip an entire plant in two weeks and, when they are at their largest, consume a leaf in less than five minutes, the press release noted. But this dependence on milkweed has made the species vulnerable. The number of monarch butterflies has decreased in the U.S. over the last 20 years, according to the U.S. Fish and Wildlife Service, and one factor is the use of pesticides that harm milkweed.
"It's interesting to think about how this would potentially impact the survival of these caterpillars, when they're crowded onto plants," University of Michigan monarch biologist D. André Green, who was not part of the study, told The New York Times. "The amount of milkweed is decreasing. This may become a bigger issue."
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Twenty-five years ago, a food called Tofurky made its debut on grocery store shelves. Since then, the tofu-based roast has become a beloved part of many vegetarians' holiday feasts.
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By Jessica Corbett
A leading environmental advocacy group marked Native American Heritage Month on Wednesday by urging President-elect Joe Biden, Vice President-elect Kamala Kamala Harris, and the entire incoming administration "to honor Indigenous sovereignty and immediately halt the Keystone XL, Dakota Access, and Line 3 pipelines."
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Returning the ‘Three Sisters’ – Corn, Beans and Squash – to Native American Farms Nourishes People, Land and Cultures
By Christina Gish Hill
Historians know that turkey and corn were part of the first Thanksgiving, when Wampanoag peoples shared a harvest meal with the pilgrims of Plymouth plantation in Massachusetts. And traditional Native American farming practices tell us that squash and beans likely were part of that 1621 dinner too.
Abundant Harvests<p>Historically, Native people throughout the Americas bred indigenous plant varieties specific to the growing conditions of their homelands. They selected seeds for many different traits, such as <a href="https://emergencemagazine.org/story/corn-tastes-better/" target="_blank" rel="noopener noreferrer">flavor, texture and color</a>.</p><p>Native growers knew that planting corn, beans, squash and sunflowers together produced mutual benefits. Corn stalks created a trellis for beans to climb, and beans' twining vines secured the corn in high winds. They also certainly observed that corn and bean plants growing together tended to be healthier than when raised separately. Today we know the reason: Bacteria living on bean plant roots pull nitrogen – an essential plant nutrient – from the air and <a href="http://www.tilthalliance.org/learn/resources-1/almanac/october/octobermngg" target="_blank" rel="noopener noreferrer">convert it to a form that both beans and corn can use</a>.</p><p>Squash plants contributed by shading the ground with their broad leaves, preventing weeds from growing and retaining water in the soil. Heritage squash varieties also had spines that discouraged deer and raccoons from visiting the garden for a snack. And sunflowers planted around the edges of the garden created a natural fence, protecting other plants from wind and animals and attracting pollinators.</p><p>Interplanting these agricultural sisters produced bountiful harvests that sustained large Native communities and <a href="http://dx.doi.org/10.1353/eam.2015.0016" target="_blank">spurred fruitful trade economies</a>. The first Europeans who reached the Americas were shocked at the abundant food crops they found. My research is exploring how, 200 years ago, Native American agriculturalists around the Great Lakes and along the Missouri and Red rivers fed fur traders with their diverse vegetable products.</p>
Displaced From the Land<p>As Euro-Americans settled permanently on the most fertile North American lands and acquired seeds that Native growers had carefully bred, they imposed policies that <a href="https://doi.org/10.1086/ahr/87.2.550" target="_blank">made Native farming practices impossible</a>. In 1830 President Andrew Jackson signed the <a href="https://guides.loc.gov/indian-removal-act" target="_blank">Indian Removal Act</a>, which made it official U.S. policy to force Native peoples from their home locations, pushing them onto subpar lands.</p><p>On reservations, U.S. government officials discouraged Native women from cultivating anything larger than small garden plots and pressured Native men to practice Euro-American style monoculture. Allotment policies assigned small plots to nuclear families, further limiting Native Americans' access to land and preventing them from using communal farming practices.</p><p>Native children were forced to attend boarding schools, where they had no opportunity to <a href="https://doi.org/10.5749/jamerindieduc.57.1.0145" target="_blank">learn Native agriculture techniques or preservation and preparation of Indigenous foods</a>. Instead they were forced to eat Western foods, turning their palates away from their traditional preferences. Taken together, these policies <a href="https://kansaspress.ku.edu/978-0-7006-0802-7.html" target="_blank" rel="noopener noreferrer">almost entirely eradicated three sisters agriculture</a> from Native communities in the Midwest by the 1930s.</p>
Reviving Native Agriculture<p>Today Native people all over the U.S. are working diligently to <a href="https://www.oupress.com/books/15107980/indigenous-food-sovereignty-in-the-united-sta" target="_blank" rel="noopener noreferrer">reclaim Indigenous varieties of corn, beans, squash, sunflowers and other crops</a>. This effort is important for many reasons.</p><p>Improving Native people's access to healthy, culturally appropriate foods will help lower rates of <a href="https://www.cdc.gov/vitalsigns/aian-diabetes/index.html" target="_blank">diabetes</a> and <a href="https://www.apa.org/pi/oema/resources/ethnicity-health/native-american/obesity" target="_blank">obesity</a>, which affect Native Americans at disproportionately high rates. Sharing traditional knowledge about agriculture is a way for elders to pass cultural information along to younger generations. Indigenous growing techniques also protect the lands that Native nations now inhabit, and can potentially benefit the wider ecosystems around them.</p>
By Jake Johnson
Amid reports that oil industry-friendly former Energy Secretary Ernest Moniz remains under consideration to return to his old post in the incoming Biden administration, a diverse coalition of environmental groups is mobilizing for an "all-out push" to keep Moniz away from the White House and demand a cabinet willing to boldly confront the corporations responsible for the climate emergency.
Anger, anxiety, overwhelm … climate change can evoke intense feelings.
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