- News Home
6 March 2014 1:04 pm ,
Vol. 343 ,
Two studies show that eating a diet low in protein and high in carbohydrates is linked to a longer, healthier life, and...
Considered an icon of conservation science, researchers at World Wildlife Fund (WWF) headquarters in Washington, D.C.,...
The new atlas, which shows the distribution of important trace metals and other substances, is the first product of...
Early in April, the first of a fleet of environmental monitoring satellites will lift off from Europe's spaceport in...
Since 2000, U.S. government health research agencies have spent almost $1 billion on an effort to churn out thousands...
Magdalena Koziol, a former postdoc at Yale University, was the victim of scientific sabotage. Now, she is suing the...
Antiretroviral drugs can protect people from becoming infected by HIV. But so-called pre-exposure prophylaxis, or PrEP...
- 6 March 2014 1:04 pm , Vol. 343 , #6175
- About Us
ScienceShot: Why Butterflies Sleep Together
20 March 2012 8:01 pm
When it's time to settle in for the night, red postman butterflies (Heliconius erato) often roost in groups of four or five. To figure out why, researchers hung several thousand fake versions of the insects around the forest in Panama and Costa Rica. To measure bird attacks, they counted beak marks on the dummies' modeling-clay bodies and wax-coated paper wings. Individuals perched alone or in pairs were more than six times as likely to be attacked as were models perched in groups of five. The effect went beyond a simple sharing of risk among group members: Each roost of five, considered as a unit, was less likely than a singleton to experience an attack, the team reports online today in the Proceedings of the Royal Society B. The researchers argue that the butterflies' bright markings, which advertise their toxicity to predators, are more effective when amplified in a group.
See more ScienceShots.