Spider webs are great at catching flying insects, but they’re an inviting target for walking ones. The spider sits pretty in the middle of its home, surrounded by the pre-packaged morsels of the insects it has caught. It’s an all-you-can-eat buffet, and ants should easily be able to raid it. Ants are excellent predators, they hunt in large numbers, and they can negotiate their way along the non-stick parts of the web. And yet, there are very few reports of ants successfully pillaging spider webs. Why?

Shichang Zhang has found one possible answer: some spiders lace their silk with an ant-repelling chemical. Their sticky webs, which so effectively trap some insects, can also deter others.

The golden orb-web spider (Nephila