Department of Anthropology, University of Wisconsin-Madison
Saturday 8:15-8:30, Ballroom C
Human cultural, dietary and foraging behaviors rely upon information from the senses. Primates vary in auditory sensitivities across a range of frequencies, in the number and types of olfactory receptors, in color sensitivity, and in the types of chemicals they can taste, all reflective of ecological or social requirements. Likewise, some sensory traits differ between humans and chimpanzees, or vary within and among human populations. Here I focus on the genetic aspects of sensory variation in humans and the known sensory innovations in human evolution. These include recurrent positive selection on genes related to inner ear function, losses and duplications of olfactory receptors, and allelic variants responsible for taste polymorphisms. Most nucleotide sites that differ between humans and other hominoids, or that vary among humans, are represented in ancient DNA evidence from the Vindija Neandertals and from Denisova Cave. Neandertals and Denisovans show a substantial number of olfactory receptor losses relative to humans, but comparable in scale to those found among human populations. Of those genes related to hearing that show evidence of positive selection in humans relative to the great apes, nearly all known human-specific changes are also found in the Neandertal and Denisova genomes. These genetic observations related to the inner ear are consistent with morphological evidence from the middle ear that Middle Pleistocene people had adapted toward the humanlike condition, although not identical to the present human state. These comparisons may contribute to our understanding of the Umwelt of these ancient people.