A cladistic analysis of ammonoids spanning the Permian–Triassic boundary tests survival and turnover in that sampled interval; it neither covers all Ammonoidea nor fixes their origin and extinction endpoints.
claim:taxon:ammonoideaAmmonoidea
A cladistic analysis of ammonoids spanning the Permian–Triassic boundary tests survival and turnover in that sampled interval; it neither covers all Ammonoidea nor fixes their origin and extinction endpoints. This navigation entry is not a phylogeny or a complete taxon dossier.
Represented range274.4–250.8 Ma
Content packagemolluscs-brachiopods
PBDBtxn:14505
Evidence boundary
Automated checks cover structure, identifiers, translations and links only; maintainer and external expert review are not complete.
Claim ledger
McGowan and Smith sample Middle–Late Permian and Induan ammonoids across the Permian–Triassic boundary, supporting a Roadian-to-end-Induan study window of 274.4–250.8 Ma rather than the full Ammonoidea range, a divergence date or continuous global occupancy.
claim:taxon:ammonoidea:source-bounded-range-rc50Known limits
- A missing branch or fossil occurrence does not imply biological absence. Internal nodes are not calibrated divergence estimates.
References
- Ammonoids across the Permian/Triassic boundary: a cladistic perspectiveMcGowan, A.J.; Smith, A.B. · 2007 · DOI 10.1111/j.1475-4983.2007.00653.x
- International Chronostratigraphic Chart v2026/06Cohen, K.M.; Harper, D.A.T.; Gibbard, P.L.; Car, N. · 2026 · DOI 10.18814/epiiugs/2025/025001
- Open Tree of Life web servicesOpenTreeOfLife Project
- The Paleobiology Database application programming interfacePeters, S.E.; McClennen, M. · 2016 · DOI 10.1017/pab.2015.39
- Denormalized occurrence and taxon tables of the Paleobiology DatabaseThe Paleobiology Database Community; Kocsis, Á.T. · 2026 · DOI 10.5281/zenodo.21620933