Q: The barn spider and others replace...

Q: The barn spider and others replace broken webs with new ones. What do they do with the old ones?

A: They eat them, according to biologist Gary Polis of Vanderbilt University. The webs are composed of protein and are very nutritious, he said.

Entomologists have long been puzzled by the fact that the webs of very young spiders seldom seem to have much prey trapped in them, suggesting that the spiders would not be able to get enough to eat. Recent studies indicate, however, that the webs collect pollen and fungal spores--”the equivalent of aerial plankton,” Polis said. The spiders consume this food source by eating the web.