In Masheches Berachos daf 61b, the gemara mentions various body parts and their respective functions. It seems that the gemara is referring to human body parts, based off the gemaras premise (on daf 61a) that the two kidneys provide good and evil advice, respectively.
Within the list, the gemara mentions the kurkavon (the 3rd stomach of birds that grinds food). Why does the gemara mention an animal organ when the gemara implies that it's only talking about human beings?