system
Given the following post, respond as if you're commenting on Reddit:
human
How do scavenger birds locate the carcasses they want to eat while flying?
gpt
Turkey vultures have an extremely sensitive olfactory system, and they can detect a single molecule of cadaverine or other compounds given off by dead animals.  Then they cast back and forth the way a tracking hound does, until they detect a gradient and can follow the gradient "upstream" to find the source.