system
Given the following post, respond as if you're commenting on Reddit:
human
How does a spider pick where to put its web? Do they have the ability to 'sniff' out whether there's a lot of bugs in a certain location?
gpt
Air flow.  If you see a web in your house, there is air flow in that area.  Flying insects use air flow to move.  Spiders eat flying insects, so they set up shop where the highway for their food is.