H-GSP 18507 is the holotype of Ambulocetus natans and is routed under Ambulocetidae; that placement does not identify a direct cetacean ancestor.
claim:taxon:ambulocetus:taxonomyAmbulocetus
Partial skeleton H-GSP 18507 combines large weight-bearing limbs with vertebral and hind-limb anatomy used to model amphibious swimming.
Represented range48–47 Ma
Content packagecetartiodactyla
PBDBtxn:36660
Evidence boundary
Automated checks cover structure, identifiers, translations and links only; maintainer and external expert review are not complete.
Claim ledger
The profile is restricted to the Kuldana Formation occurrence in Pakistan and does not imply a complete dispersal range.
claim:taxon:ambulocetus:biogeographyRobust anatomy supports amphibious predation and locomotor models, while exact swimming style, prey and land performance were not directly observed.
claim:taxon:ambulocetus:ecologyH-GSP 18507 preserves a partial skull, vertebral column and substantial fore- and hind-limb material documenting an anatomical mosaic.
claim:taxon:ambulocetus:morphologyThe 48–47 Ma envelope is a formation-level context for the holotype, not a genus-wide FAD, LAD, cetacean transition duration or direct date.
claim:taxon:ambulocetus:fossil-rangeKnown limits
- A missing branch or fossil occurrence does not imply biological absence. Internal nodes are not calibrated divergence estimates.
References
- Fossil evidence for the origin of aquatic locomotion in archaeocete whalesThewissen, J.G.M.; Hussain, S.T.; Arif, M. · 1994 · DOI 10.1126/science.263.5144.210
- 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