ArticleBiology letters2015
Resurrecting embryos of the tuatara, Sphenodon punctatus, to resolve vertebrate phallus evolution.
Article in Biology letters, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers.
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13 citing papers in PubMed, 39 citations in OpenAlex.
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- The exquisitely preserved integument of Psittacosaurus and the scaly skin of ceratopsian dinosaurs.Communications biology · 2022Review
- 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
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- Theories, laws, and models in evo-devo.Journal of experimental zoology. Part B, Molecular and developmental evolution · 2022Review
- Single cell transcriptomic analysis of external genitalia reveals complex and sexually dimorphic cell populations in the early genital tubercle.Developmental biology · 2021Article
- Meeting report on the NIDDK/AUA Workshop on Congenital Anomalies of External Genitalia: challenges and opportunities for translational research.Journal of pediatric urology · 2020Review
- Article
- Sesamoid bones in tuatara (Sphenodon punctatus) investigated with X-ray microtomography, and implications for sesamoid evolution in Lepidosauria.Journal of morphology · 2017Article
- The Genetic Basis of Baculum Size and Shape Variation in Mice.G3 (Bethesda, Md.) · 2016Article
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3 authors at 2 institutions in 1 country.
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Abstract
The breadth of anatomical and functional diversity among amniote external genitalia has led to uncertainty about the evolutionary origins of the phallus. In several lineages, including the tuatara, Sphenodon punctatus, adults lack an intromittent phallus, raising the possibility that the amniote ancestor lacked external genitalia and reproduced using cloacal apposition. Accordingly, a phallus may have evolved multiple times in amniotes. However, similarities in development across amniote external genitalia suggest that the phallus may have a single evolutionary origin. To resolve the evolutionary history of amniote genitalia, we performed three-dimensional reconstruction of Victorian era tuatara embryos to look for embryological evidence of external genital initiation. Despite the absence of an intromittent phallus in adult tuataras, our observations show that tuatara embryos develop genital anlagen. This illustrates that there is a conserved developmental stage of external genital development among all amniotes and suggests a single evolutionary origin of amniote external genitalia.
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