system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do spiders remain stationary in one location for such a long amount of time?

Why do many spiders stay in the same location, without moving, for days, weeks, even months?
gpt
They're conserving energy. Many spiders are ambush predators. They build a trap (their web), and attack prey that falls into the trap. Moving around unnecessarily burns energy they could instead conserve to keep them alive longer between prey, and attack more energetically when it arrives.