ArticleIntegrative and comparative biology2016
The Baculum was Gained and Lost Multiple Times during Mammalian Evolution.
Article in Integrative and comparative biology, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 26 papers.
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Who cites it
26 citing papers in PubMed.
- Radiographic reference values for canine baculum length: association with body-weight category in dogs aged at least 1 year.Veterinary research communications · 2026Article
- Testing for Functional Adaptation in a Genital Bone: Baculum Size, Shape, and Microstructure Show Little Plastic Response to Mating Across Five Rodent Species.Integrative organismal biology (Oxford, England) · 2026Article
- Commentary: The missing sabertooth baculum-At what point might the absence of evidence reasonably be considered evidence of absence?Anatomical record (Hoboken, N.J. : 2007) · 2025Article
- The Human Penile Fibro-Vascular Assembly Requires the Integrity of Ten Fibro-Ligaments.Life (Basel, Switzerland) · 2025Article
- Genetic disruption of the baculum compromises the ability of male mice to copulate.PLoS genetics · 2025Article
- First description of the baubellum in the spectacled bear Tremarctos ornatus (Mammalia: Ursidae).Journal of anatomy · 2024Article
- The Italian Society of Andrology and Sexual Medicine (SIAMS), along with ten other Italian Scientific Societies, guidelines on the diagnosis and management of erectile dysfunction.Journal of endocrinological investigation · 2023Article
- Baculum shape complexity correlates to metrics of post-copulatory sexual selection in Musteloidea.Journal of morphology · 2023Article
- Fossil bacula of five species of Borophaginae (Family: Canidae): Implications for their reproductive biology.PloS one · 2023Article
- Female Genital Variation Far Exceeds that of Male Genitalia: A Review of Comparative Anatomy of Clitoris and the Female Lower Reproductive Tract in Theria.Integrative and comparative biology · 2022Article
- Evolution of genes involved in the unusual genitals of the bear macaque,Ecology and evolution · 2022Article
- The baculum affects paternity success of first but not second males in house mouse sperm competition.BMC ecology and evolution · 2021Article
- Diversification, Introgression, and Rampant Cytonuclear Discordance in Rocky Mountains Chipmunks (Sciuridae: Tamias).Systematic biology · 2021Article
- Developmental and sexual dimorphic atlas of the prenatal mouse external genitalia at the single-cell level.Proceedings of the National Academy of Sciences of the United States of America · 2021Article
- The ultimate database to (re)set the evolutionary history of primate genital bones.Scientific reports · 2021Article
- 3D reconstruction and histopathological analyses on murine corporal body.Reproductive medicine and biology · 2021Article
- Postcopulatory sexual selection and the evolution of shape complexity in the carnivoran baculum.Proceedings. Biological sciences · 2020Article
- Discrete Hedgehog Factor Expression and Action in the Developing Phallus.International journal of molecular sciences · 2020Article
- A 3D journey on virtual surfaces and inner structure of ossa genitalia in Primates by means of a non-invasive imaging tool.PloS one · 2020Article
- Erectile dysfunction and the baculum.Evolution, medicine, and public health · 2019Article
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Authors and funding
5 authors.
Funding
Abstract
The rapid evolution of male genitalia is a nearly ubiquitous pattern across sexually reproducing organisms, likely driven by the evolutionary pressures of male-male competition, male-female interactions, and perhaps pleiotropic effects of selection. The penis of many mammalian species contains a baculum, a bone that displays astonishing morphological diversity. The evolution of baculum size and shape does not consistently correlate with any aspects of mating system, hindering our understanding of the evolutionary processes affecting it. One potential explanation for the lack of consistent comparative results is that the baculum is not actually a homologous structure. If the baculum of different groups evolved independently, then the assumption of homology inherent in comparative studies is violated. Here, we specifically test this hypothesis by modeling the presence/absence of bacula of 954 mammalian species across a well-established phylogeny and show that the baculum evolved a minimum of nine times, and was lost a minimum of ten times. Three different forms of bootstrapping show our results are robust to species sampling. Furthermore, groups with a baculum show evidence of higher rates of diversification. Our study offers an explanation for the inconsistent results in the literature, and provides insight into the evolution of this remarkable structure.
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