…not even hot peppers.


Capsaicin is tasteless and odorless.  As mammals, we feel the pain (so good!) of capsaicin in certain pain receptors (or nociceptors — L. nocere, harm; capere, to take hold — source).   And not just on our tongues, and that’s all that needs to be mentioned with respect to that.   But birds have very little sensitivity to capsaicin.  It’s been a good way for chili plants to screen out the less desirable fruit consumers:  those who can’t fly, hence would be pretty useless in dispersing the seeds.  It doesn’t discourage us, of course, and we haven’t been able to fly until recently.  But we farm, so we’re OK.


Scoville scale @Wikipedia