system
Given the following post, respond as if you're commenting on Reddit:
human
Is the spiciness of peppers intended to persuade or dissuade animals from eating them?
gpt
"The seeds of Capsicum plants are dispersed predominantly by birds: in birds, the TRPV1 channel does not respond to capsaicin or related chemicals in birds (avian vs mammalian TRPV1 show functional diversity and selective sensitivity). This is advantageous to the plant, as chili pepper seeds consumed by birds pass through the digestive tract and can germinate later, whereas mammals have molar teeth which destroy such seeds and prevent them from germinating. Thus, natural selection may have led to increasing capsaicin production because it makes the plant less likely to be eaten by animals that do not help it reproduce."

Source: Tewksbury, J. J.; Nabhan, G. P. (2001). "Seed dispersal. Directed deterrence by capsaicin in chilies". Nature 412 (6845): 403–404.