Strong links between genomic and anatomical diversity in both mammalian olfactory chemosensory systems.
Mammalian olfaction comprises two chemosensory systems: the odorant-detecting main olfactory system (MOS) and the pheromone-detecting vomeronasal system (VNS). Mammals are diverse in their anatomical and genomic emphases on olfactory chemosensation, including the loss or reduction of these systems in some orders. Despite qualitative evidence linking the genomic evolution of the olfactory systems to specific functions and phenotypes, little work has quantitatively tested whether the genomic aspects of the mammalian olfactory chemosensory systems are correlated to anatomical diversity. We show that the genomic and anatomical variation in these systems is tightly linked in both the VNS and the MOS, though the signature of selection is different in each system. Specifically, the MOS appears to vary based on absolute organ and gene family size while the VNS appears to vary according to the relative proportion of functional genes and relative anatomical size and complexity. Furthermore, there is little evidence that these two systems are evolving in a linked fashion. The relationships between genomic and anatomical diversity strongly support a role for natural selection in shaping both the anatomical and genomic evolution of the olfactory chemosensory systems in mammals.
Program in Anthropology, The Graduate Center, City University of New York, , 365 Fifth Avenue, New York, NY 10016-4309, USA, Program in Biology, The Graduate Center, City University of New York, , 365 Fifth Avenue, New York, NY 10016-4309, USA, New York Consortium in Evolutionary Primatology (NYCEP), , New York, NY, USA, Department of Anthropology, Hunter College, City University of New York, , 695 Park Avenue, New York, NY 10065-5024, USA.
Eva C
EC
Garrett
Michael E
ME
Steiper
D000818:Animals; D014644:Genetic Variation; D016018:Least-Squares Analysis; D008322:Mammals / Q000033:anatomy & histology / Q000235:genetics / Q000502:physiology*; D009831:Olfactory Mucosa / Q000033:anatomy & histology / Q000502:physiology*; D055696:Olfactory Perception / Q000235:genetics*; D010802:Phylogeny; D019147:Vomeronasal Organ / Q000033:anatomy & histology / Q000502:physiology*
anatomical evolution; genomic evolution; mammalian evolution; olfaction