Q: I often see spider webs across...

Q: I often see spider webs across a trail five feet or more above the ground. How do the spiders get across to attach the first strand?

A: They don’t, according to biologist Gary Polis of Vanderbilt University. Instead, they sit and release sticky silk out of the spinnerets on the back of their abdomen. The silk plays out, catches in the wind, and eventually sticks to something. The spider can then use it to build the rest of its web.