SVP 2021 abstracts – 04: Mysticetes are still not related to odontocetes

Rohlicek and Boessenecker 2021 reported,
“The Oligocene was a time of key anatomical innovations in cetaceans as mysticetes and odontocetes diverged and diversified from ancestral whale lineages.”

When you add taxa, the traditional clade, ‘Cetacea’ splits apart. Mysticetes and Odontocetes are convergent, not related. We’ve known this since 2016. These two clade split apart when their ancestors were both tree shrews in the Jurassic.

“We assessed previously unpublished fossils from the Sooke Formation (late Oligocene) of Vancouver Island, British Columbia, Canada, in the Royal BC Museum collections. Vancouver
Island is the only location in Canada to preserve Oligocene cetacean fossils, and as such has the potential to contribute new data to understanding Oligocene whale evolution.”

Usually the first step is to find fossils. However, when the phylogeny needs a little housekeeping, the first step now is to add taxa to current studies.
Then… go out looking for other specimens.

Rohlicek E and Boesseneckergo on to describe several individual bones and their possible associations, then finish with a suggestion for future exploration.

Paleontologists have four jobs: To find the bones. To expose the bones (increasingly with µCT scanning). To describe the bones. To nest their taxa in a cladogram. The last job can be problematic when paleontologists borrow cladograms from others and don’t have their own cladogram, one with the authority (= large enough to minimize taxon exclusion) of the LRT.

That’s why the large reptile tree is here for you. IF you wonder if you included a wide enough gamut of taxa, check the LRT. It’s nothing but a tool that gets better with every new taxon.

References
Rohlicek E and Boessenecker R 2021. Evidence for Oligocene cetacean diversity in the Sooke Formation (Carmanah Group) of Vancouver Island, British Columbia, Canada. Journal of Vertebrate Paleontology abstracts.