The pineal body, known to regulate sleep patterns in humans, is thought to produce the hormones involved in hibernation and aestivation in amphibians.
ðə pˈɪniəl bˈɑːdi, nˈoʊn tə ɹˈɛɡjʊlˌeɪt slˈiːp pˈætɚnz ɪn hjˈuːmənz, ɪz θˈɔːt tə pɹədˈuːs ðə hˈoːɹmoʊnz ɪnvˈɑːlvd ɪn hˌaɪbɚnˈeɪʃən ænd ˌiːstɪvˈeɪʃən ɪn æmfˈɪbiənz.