Very hungry and angry, caterpillars head-butt to get what they want — ScienceDaily

Inspired by his own butterfly garden at home, a Florida Atlantic University neuroscientist got a unique look at how monarch butterfly (Danaus plexippus) caterpillars behave when food is scarce. The results look something like a combination of boxing and “bumper” cars.

With less access to their favorite food — milkweed — they go from docile to domineering, aggressively head-butting, lunging and knocking aside other caterpillars to ensure their own survival. And, they are most aggressive right before the final stages of their metamorphosis. A lack of nutrition during larval stages has been shown to delay larval development as well as reduce adult body size, reproductive performance and lifespan.

“Aggression is common in insects, including fruit flies, where single-pheromone receptors or single genes have been shown to trigger their aggression,” said Alex Keene, Ph.D., lead author and a professor of biological sciences, FAU’s Charles E. Schmidt College of Science. “I decided

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Hungry plants rely on their associated bacteria to mobilize unavailable iron — ScienceDaily

In nature, healthy plants are awash with bacteria and other microbes, mostly deriving from the soil they grow in. This community of microbes, termed the plant microbiota, is essential for optimal plant growth and protects plants from the harmful effects of pathogenic microorganisms and insects. The plant root microbiota is also thought to improve plant performance when nutrient levels are low, but concrete examples of such beneficial interactions remain scarce. Iron is one of the most important micronutrients for plant growth and productivity. Although abundant in most soils, iron’s poor availability often limits plant growth, as it is found in forms that cannot be taken up by plants. Thus, adequate crop yields often necessitate the use of chemical fertilizers, which can be ecologically harmful in excessive application. Now, MPIPZ researchers led by Paul Schulze-Lefert have uncovered a novel strategy employed by plants to overcome this problem: they release substances from

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Hungry screwworms eat livestock alive while thrips transmit viruses — ScienceDaily

The University of Cincinnati is decoding the genetics of agricultural pests in projects that could help boost crop and livestock production to feed millions more people around the world.

Joshua Benoit, an associate professor in UC’s College of Arts and Sciences, contributed to genetic studies of New World screwworms that feed on livestock and thrips, tiny insects that can transmit viruses to tomatoes and other plants.

It’s the latest international collaboration for Benoit, who previously sequenced the DNA for genomes of dreaded creatures such as bedbugs.

Just in time for Halloween, Benoit’s new study subject is no less creepy. The New World screwworm’s Latin name means “man-eater.” These shiny blue flies with pumpkin-orange eyes lay up to 400 eggs in open cuts or sores of cattle, goats, deer and other mammals. Emerging larvae begin gnawing away on their hosts, feeding on living and dead tissue and creating ghastly wounds.

“Sometimes

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