This spider doesn’t run or hide when danger strikes. Instead, it builds a fake version of itself — and predators fall for it.

Webs can be decorated with decoys, fine-tuned like guitars—and hold secrets about evolution. A Cyclosa spider is camouflaged on a web with debris attached to make itself less visible at the Los Amigos ...

Ecologists Andrew Davis and Benjamin Frick have crisscrossed the United States studying everything from monarch butterflies to house finches. But when a giant, neon-yellow spider arrived in the U.S.