Davydenko et al. 2021
report the discovery of new giant basilosaurid from Ukraine.
From the abstract:
“The earliest fully aquatic cetaceans arose during the Middle Eocene; however, the earliest stage of their divergence is obscure. Here, we provide a detailed redescription of an unusual early cetacean, “Platyosphys einori”, from the Late Eocene of Ukraine (37.8–35.8 million years ago), with new data on its body size, skeletal microanatomy and suggestions on phylogenetic relationships.”
By contrast, in the large reptile tree (LRT, 1793+ taxa) the earliest stage of ‘their divergence’ (mysticetes and odontocetes) extends back to tiny tree shrews in the Jurassic. Contra public and professional opinion, whale divergence is not obscure. Taxon exclusion hampers the Davydenko et al. study.
Figure 1. Cladogram from Davydenko et al. 2021 showing how they nested Playosphys einori. See figure 2 for their proposed mysticetes (with teeth!)
Unfortunately the authors presented an outdated cladogram
that considered the former clade ‘Cetacea’ monophyletic. Their paper perpetuates an invalid hypothesis of interrelationships (Figs. 1,2) that omits the ancestors of mysticetes: desmostylians, anthracubunids, hippos, mesonychids and oreodonts. They also omit the ancestors of pakicetids: tenrecs and anagalids.
Figure 2. Portion of the cladogram from figure 1 enlarged and rotated. Llancetus and kin are not mysticete ancestors when more taxa, like Behemotops, are included in the analysis.
Sadly,
whale workers continue to perpetuate the myth that whales are monophyletic. That was invalidated several years ago here by simply adding taxa.
References
Davydenko S, Shevchenko T, Ryabokon T. et al. 2021. A Giant Eocene Whale from Ukraine Uncovers Early Cetacean Adaptations to the Fully Aquatic Life. Evol Biol (2021). https://doi.org/10.1007/s11692-020-09524-8
researchgate.net/publication/328388746_The_triple_origin_of_whales
The Pterosaur Heresies 