ArticleProceedings of the National Academy of Sciences of the United States of America2008
The oldest platypus and its bearing on divergence timing of the platypus and echidna clades.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers.
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28 citing papers in PubMed.
- Bone microstructure supports a Mesozoic origin for a semiaquatic burrowing lifestyle in monotremes (Mammalia).Proceedings of the National Academy of Sciences of the United States of America · 2025Article
- First monotreme from the Late Cretaceous of South America.Communications biology · 2023Article
- A comparative study on auditory and hyoid bones of Jurassic euharamiyidans and contrasting evidence for mammalian middle ear evolution.Journal of anatomy · 2020Article
- Conflict Resolution for Mesozoic Mammals: Reconciling Phylogenetic Incongruence Among Anatomical Regions.Frontiers in genetics · 2020Article
- Article
- Adaptive Radiation of the Flukes of the Family Fasciolidae Inferred from Genome-Wide Comparisons of Key Species.Molecular biology and evolution · 2020Article
- The platypus: evolutionary history, biology, and an uncertain future.Journal of mammalogy · 2019Article
- Pectoral girdle and forelimb musculoskeletal function in the echidna (Royal Society open science · 2018Article
- TnI Structural Interface with the N-Terminal Lobe of TnC as a Determinant of Cardiac Contractility.Biophysical journal · 2018Article
- Male Mutation Bias Is the Main Force Shaping Chromosomal Substitution Rates in Monotreme Mammals.Genome biology and evolution · 2017Article
- Article
- Comparative cranial morphology in living and extinct platypuses: Feeding behavior, electroreception, and loss of teeth.Science advances · 2016Article
- Did sex chromosome turnover promote divergence of the major mammal groups?: De novo sex chromosomes and drastic rearrangements may have posed reproductive barriers between monotremes, marsupials and placental mammals.BioEssays : news and reviews in molecular, cellular and developmental biology · 2016Review
- Palaeoneurological clues to the evolution of defining mammalian soft tissue traits.Scientific reports · 2016Article
- Resolving the evolution of the mammalian middle ear using Bayesian inference.Frontiers in zoology · 2016Article
- Transposon-mediated death of an ancestral A-23-like allele: evolution of TCR-positioning motifs in the HLA-A lineage.Immunogenetics · 2015Article
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- Review
- Article
- The natural history of sound localization in mammals--a story of neuronal inhibition.Frontiers in neural circuits · 2014Article
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5 authors.
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No grant is acknowledged in the PubMed record.
Abstract
Monotremes have left a poor fossil record, and paleontology has been virtually mute during two decades of discussion about molecular clock estimates of the timing of divergence between the platypus and echidna clades. We describe evidence from high-resolution x-ray computed tomography indicating that Teinolophos, an Early Cretaceous fossil from Australia's Flat Rocks locality (121-112.5 Ma), lies within the crown clade Monotremata, as a basal platypus. Strict molecular clock estimates of the divergence between platypus and echidnas range from 17 to 80 Ma, but Teinolophos suggests that the two monotreme clades were already distinct in the Early Cretaceous, and that their divergence may predate even the oldest strict molecular estimates by at least 50%. We generated relaxed molecular clock models using three different data sets, but only one yielded a date overlapping with the age of Teinolophos. Morphology suggests that Teinolophos is a platypus in both phylogenetic and ecological aspects, and tends to contradict the popular view of rapid Cenozoic monotreme diversification. Whereas the monotreme fossil record is still sparse and open to interpretation, the new data are consistent with much slower ecological, morphological, and taxonomic diversification rates for monotremes than in their sister taxon, the therian mammals. This alternative view of a deep geological history for monotremes suggests that rate heterogeneities may have affected mammalian evolution in such a way as to defeat strict molecular clock models and to challenge even relaxed molecular clock models when applied to mammalian history at a deep temporal scale.
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