The whale’s closest living cousin is the hippo
Molecular phylogeny places whales inside the even-toed ungulates, with hippos as their nearest living relatives.
Established2 min read
Anatomy had whales near other marine mammals or in a private order. DNA moved them. SINE insertions, rare and nearly irreversible, are shared by whales and hippos and not by other artiodactyls in the same pattern. Fossils then filled the shore: Pakicetus, Ambulocetus, legs becoming flippers.
Hippos are not ancestors of whales. They are the living sister group. The common ancestor was a terrestrial even-toed animal. One daughter waded deeper. The other stayed a herbivore with a good bite.
Caveats
- ‘Closest living relative’ is not ‘ancestor’. Both lines have been evolving since they split.
Sources
- 1Nikaido M., Rooney A. P., Okada N.. Phylogenetic Relationships among Cetartiodactyls Based on Insertions of Short and Long Interspersed Elements. Proceedings of the National Academy of Sciences 96, 1999.