In 2001, ash trees began dying in Detroit, and no one could say why. Then glittering green beetles were discovered crawling out of an ash log.

American scientists had never seen the beetles, and they reached out to experts around the world for help. A Slovakian entomologist named Eduard Jendek solved the mystery: Detroit’s ash trees were being killed by Agrilus planipennis, the emerald ash borer, an obscure species native to East Asia.

In its home forests, the emerald ash borer causes little trouble. Sadly, that is not the case in North America.

Continue reading “The Slow Process of Countering the Emerald Ash Borer” →

The Canadian tiger swallowtail caterpillar is a plump green creature that spends all its time munching leaves. It ought to be an easy meal for a bird, yet many birds pass it by.

The caterpillar is protected by a remarkable defense, researchers have found: It tricks birds into thinking it’s a snake.

The caterpillar grows concentric yellow and black rings that look like a giant pair of eyes. When the caterpillar senses a bird nearby, it quickly inflates the front part of its body, making it resemble a snake’s head.

Continue reading “Evolving a Defense, Mimics Save Themselves” →

You are what you eat, and so were your ancient ancestors. But figuring out what they actually dined on has been no easy task.

There are no Pleistocene cookbooks to consult. Instead, scientists must sift through an assortment of clues, from the chemical traces in fossilized bones to the scratch marks on prehistoric digging sticks.

Scientists have long recognized that the diets of our ancestors went through a profound shift with the addition of meat. But in the September issue of The Quarterly Review of Biology, researchers argue that another item added to the menu was just as important: carbohydrates, bane of today’s paleo diet enthusiasts.

Continue reading “For Evolving Brains, a ‘Paleo’ Diet of Carbs” →