By combining skull analyses and genetic studies, researchers assessed the sense of smell in living and fossil mammals. Results published in ‘Proceedings of the National Academy of Sciences’ (PNAS).

Take a look at the original publication: www.pnas.org/doi/10.1073/...

Congrats to the whole team, with a special mention to @quentinwildlife.bsky.social and @cecilemolinier.bsky.social, who put so much work (and 'tears of blood') into this.

7 minutes to go :)

Just a few hours left before the big reveal

Sometimes one forgets the most obvious...thanks to @quentinwildlife.bsky.social, without whom this analysis would have never taken place! Many more fossil brains are to come, watch this space!

Here is an amazing paloart by Tyler Stone

…and the accompanying models on MorphoMuseuM here:
morphomuseum.com/articles/vie...

You can find the paper here: academic.oup.com/evolut/advan...

It was for me a first opportunity to work with @muvp-eg.bsky.social , i.e., @hesham-sallam.bsky.social and @gohar.bsky.social , which was a blast! Thank you as well to @gsferreira.bsky.social and all other co-authors not on Bluesky.

Regarding the sense of smell, we basically found that no part of the olfactory apparatus was significantly reduced, indicating that these amphibious cetaceans most likely had a good nose (likely much better than ours), and that the reduction of this sense most likely came later in their evolution.

Comparing the relative volume of the brain endocast, we found that this early whale was quite brainy, which is a surprise, as the first cetaceans with big brains were so far understood to be the fully aquatic basilosaurids.

We addressed two aspects of cetacean evolution: their acquisition of a relatively big brain and the evolution of their sense of smell. As other mammals secondarily adapted to the aquatic environment, cetaceans have been assumed to reduce their sense of smell (which is air-born in this group).

We ct-scanned the skull of Protocetus atavus, an amphibious cetacean coming from the Mokattam Formation in Egypt. The inner anatomy of the skull was reconstructed, and we were able to reconstruct the brain imprint (endocast) as well as the different components of the nasal cavity.