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Abstract In mammals, social and reproductive behaviors are mediated by chemical cues encoded by hyperdiverse families of receptors expressed in the vomeronasal organ. Between species, the number of intact receptors can vary by orders of magnitude. However, the evolutionary processes behind variation in receptor number, and its link to fitness-related behaviors are not well understood. From vomeronasal transcriptomes, we discovered the first evidence of intact vomeronasal type-1 receptor (V1r) genes in bats, and we tested whether putatively functional bat receptors were orthologous to those of related taxa, or whether bats have evolved novel receptors. Instead of lineage-specific duplications, we found that bat V1rs show high levels of orthology to those of their relatives, and receptors are under comparative levels of purifying selection as non-bats. Despite widespread vomeronasal organ loss in bats, V1r copies have been retained for >65 million years. The highly conserved nature of bat V1rs challenges our current understanding of mammalian V1r function and suggests roles other than conspecific recognition or mating initiation in social behavior.
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An updated synthesis of and outstanding questions in the olfactory and vomeronasal systems in bats: Genetics asks questions only anatomy can answer
Abstract The extensive diversity observed in bat nasal chemosensory systems has been well‐documented at the histological level. Understanding how this diversity evolved and developing hypotheses as to why particular patterns exist require a phylogenetic perspective, which was first outlined in the work of anatomist Kunwar Bhatnagar. With the onset of genetics and genomics, it might be assumed that the puzzling patterns observed in the morphological data have been clarified. However, there is still a widespread mismatch of genetic and morphological correlations among bat chemosensory systems. Novel genomic evidence has set up new avenues to explore that demand more evidence from anatomical structures. Here, we outline the progress that has been made in both morphological and molecular studies on the olfactory and vomeronasal systems in bats since the work of Bhatnagar. Genomic data of olfactory and vomeronasal receptors demonstrate the strong need for further morphological sampling, with a particular focus on receiving brain regions, glands, and ducts.
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- Award ID(s):
- 2032073
- PAR ID:
- 10441976
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- The Anatomical Record
- Volume:
- 306
- Issue:
- 11
- ISSN:
- 1932-8486
- Format(s):
- Medium: X Size: p. 2765-2780
- Size(s):
- p. 2765-2780
- Sponsoring Org:
- National Science Foundation
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