system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When birds tear into the dirt looking for worms, are they just blindly excavating, or do they have some reason to believe a worm is right there?
gpt
Aviary expert here. Birds can tell the sensation of creatures moving beneath their feet. Earth is one of the best conduits of movement, so the vibrations of animals such as worms can be felt through their claws and talons, travelling through their legs and into their bones, eventually vibrating into their skulls. This sensation allows them to pinpoint the movement of any animal, so they can then aim their beaks to strike at the exact moment any creature comes closest to the surface.

TLDR: Yes birds know what they're doing, it's not down to chance.