ArticleNature communications2019
An Early Cretaceous enantiornithine (Aves) preserving an unlaid egg and probable medullary bone.
Article in Nature communications, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
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Who cites it
15 citing papers in PubMed.
- Hyperelongate ornamental tail feathers in a new early Cretaceous enantiornithine bird.PloS one · 2026Article
- Insights into the early evolution of modern avian physiology from fossilized soft tissues from the Mesozoic.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- Taphonomic variation in vascular remains from Mesozoic non-avian dinosaurs.Scientific reports · 2025Article
- New enantiornithine diversity in the Hell Creek Formation and the functional morphology of the avisaurid tarsometatarsus.PloS one · 2024Article
- Palaeoecological deductions from osteohistology.Biology letters · 2023Review
- Properties, Genetics and Innate Immune Function of the Cuticle in Egg-Laying Species.Frontiers in immunology · 2022Review
- Forty new specimens ofPeerJ · 2022Article
- The diet of early birds based on modern and fossil evidence and a new framework for its reconstruction.Biological reviews of the Cambridge Philosophical Society · 2021Review
- Dinosaur senescence: a hadrosauroid with age-related diseases brings a new perspective of "old" dinosaurs.Scientific reports · 2021Article
- Keratan sulfate as a marker for medullary bone in fossil vertebrates.Journal of anatomy · 2021Article
- The Making of Calibration Sausage Exemplified by Recalibrating the Transcriptomic Timetree of Jawed Vertebrates.Frontiers in genetics · 2021Article
- Article
- Evolution and distribution of medullary bone: evidence from a new Early Cretaceous enantiornithine bird.National science review · 2020Article
- Identifying medullary bone in extinct avemetatarsalians: challenges, implications and perspectives.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2020Article
- Article
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8 authors.
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Abstract
Understanding non-crown dinosaur reproduction is hindered by a paucity of directly associated adults with reproductive traces. Here we describe a new enantiornithine, Avimaia schweitzerae gen. et sp. nov., from the Lower Cretaceous Xiagou Formation with an unlaid egg two-dimensionally preserved within the abdominothoracic cavity. Ground-sections reveal abnormal eggshell proportions, and multiple eggshell layers best interpreted as a multi-layered egg resulting from prolonged oviductal retention. Fragments of the shell membrane and cuticle are both preserved. SEM reveals that the cuticle consists of nanostructures resembling those found in neornithine eggs adapted for infection-prone environments, which are hypothesized to represent the ancestral avian condition. The femur preserves small amounts of probable medullary bone, a tissue found today only in reproductively active female birds. To our knowledge, no other occurrence of Mesozoic medullary bone is associated with indications of reproductive activity, such as a preserved egg, making our identification unique, and strongly supported.
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