ArticleNature ecology & evolution2023
Extended embryo retention and viviparity in the first amniotes.
Article in Nature ecology & evolution, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.
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Who cites it
5 citing papers in PubMed, 14 citations in OpenAlex.
- Evolution of the reptile spine reveals independent trajectories to axial skeletal complexity in amniotes.Nature communications · 2026Article
- Live birth in lizards: A process-based model for the roles of temperature, behavior, and life-history.Evolution letters · 2026Article
- Article
- Palaeohistology of Macrospondylus bollensis (Crocodylomorpha: Thalattosuchia: Teleosauroidea) from the Posidonienschiefer Formation (Toarcian) of Germany, with insights into life history and ecology.Anatomical record (Hoboken, N.J. : 2007) · 2025Article
- Rethinking the egg.National science review · 2024Article
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Authors and funding
8 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The amniotic egg with its complex fetal membranes was a key innovation in vertebrate evolution that enabled the great diversification of reptiles, birds and mammals. It is debated whether these fetal membranes evolved in eggs on land as an adaptation to the terrestrial environment or to control antagonistic fetal-maternal interaction in association with extended embryo retention (EER). Here we report an oviparous choristodere from the Lower Cretaceous period of northeast China. The ossification sequence of the embryo confirms that choristoderes are basal archosauromorphs. The discovery of oviparity in this assumed viviparous extinct clade, together with existing evidence, suggests that EER was the primitive reproductive mode in basal archosauromorphs. Phylogenetic comparative analyses on extant and extinct amniotes suggest that the first amniote displayed EER (including viviparity).
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Registered trials
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