ArticleProceedings of the National Academy of Sciences of the United States of America2009
Molecules, morphology, and ecology indicate a recent, amphibious ancestry for echidnas.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 45 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
45 citing papers in PubMed, 5 citations in OpenAlex.
- Article
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- Comparative Genomics Reveals the Ancestral Recombination Landscape of Placental Mammals.bioRxiv : the preprint server for biology · 2026Article
- Synapsids and sensitivity: Broad survey of tetrapod trigeminal canal morphology supports an evolutionary trend of increasing facial tactile specialization in the mammal lineage.Anatomical record (Hoboken, N.J. : 2007) · 2026Article
- Mechanisms driving resistance to oxidative stress during endometrial stromal cell decidualization†.Biology of reproduction · 2026Review
- 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
- Pseudogenization of NK3 homeobox 2 (Open biology · 2024Article
- Phylogenetic Biodiversity Metrics Should Account for Both Accumulation and Attrition of Evolutionary Heritage.Systematic biology · 2024Article
- Color vision evolution in egg-laying mammals: insights from visual photoreceptors and daily activities of Australian echidnas.Zoological letters · 2024Article
- A century of exercise physiology: concepts that ignited the study of human thermoregulation. Part 4: evolution, thermal adaptation and unsupported theories of thermoregulation.European journal of applied physiology · 2024Review
- Variation and convergence in the morpho-functional properties of the mammalian neocortex.Frontiers in systems neuroscience · 2024Review
- A century of exercise physiology: concepts that ignited the study of human thermoregulation. Part 1: Foundational principles and theories of regulation.European journal of applied physiology · 2023Review
- EchidnaCSI: Engaging the public in research and conservation of the short-beaked echidna.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
- A chromosome-level genome of Antechinus flavipes provides a reference for an Australian marsupial genus with male death after mating.Molecular ecology resources · 2022Article
- Article
- The Making of Calibration Sausage Exemplified by Recalibrating the Transcriptomic Timetree of Jawed Vertebrates.Frontiers in genetics · 2021Article
- Evolution of the Avian Eggshell Biomineralization Protein Toolkit - New Insights From Multi-Omics.Frontiers in genetics · 2021Review
- Conflict Resolution for Mesozoic Mammals: Reconciling Phylogenetic Incongruence Among Anatomical Regions.Frontiers in genetics · 2020Article
- The platypus: evolutionary history, biology, and an uncertain future.Journal of mammalogy · 2019Article
- Disease Heritability Enrichment of Regulatory Elements Is Concentrated in Elements with Ancient Sequence Age and Conserved Function across Species.American journal of human genetics · 2019Article
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Authors and funding
3 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The semiaquatic platypus and terrestrial echidnas (spiny anteaters) are the only living egg-laying mammals (monotremes). The fossil record has provided few clues as to their origins and the evolution of their ecological specializations; however, recent reassignment of the Early Cretaceous Teinolophos and Steropodon to the platypus lineage implies that platypuses and echidnas diverged >112.5 million years ago, reinforcing the notion of monotremes as living fossils. This placement is based primarily on characters related to a single feature, the enlarged mandibular canal, which supplies blood vessels and dense electrosensory receptors to the platypus bill. Our reevaluation of the morphological data instead groups platypus and echidnas to the exclusion of Teinolophos and Steropodon and suggests that an enlarged mandibular canal is ancestral for monotremes (partly reversed in echidnas, in association with general mandibular reduction). A multigene evaluation of the echidna-platypus divergence using both a relaxed molecular clock and direct fossil calibrations reveals a recent split of 19-48 million years ago. Platypus-like monotremes (Monotrematum) predate this divergence, indicating that echidnas had aquatically foraging ancestors that reinvaded terrestrial ecosystems. This ecological shift and the associated radiation of echidnas represent a recent expansion of niche space despite potential competition from marsupials. Monotremes might have survived the invasion of marsupials into Australasia by exploiting ecological niches in which marsupials are restricted by their reproductive mode. Morphology, ecology, and molecular biology together indicate that Teinolophos and Steropodon are basal monotremes rather than platypus relatives, and that living monotremes are a relatively recent radiation.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.