My Kingdom for a Neanderthal Cribriform Plate of Ethmoid!

     At the risk of looking like a dumb shit I’m going to assume my position waaaayyyy out on a limb and ask for help from you, the reader. 

Click for photo credit.

As you know I think it likely that the Neanderthal mid-facial skeleton evolved alongside an increased species dependence on carnivory. I’ve tried every way I know to gain access to information about the skeletal correlates of olfaction. Happily, I’ve discovered a very small literature on the matter. The good news is that there’s a skeletal correlate of olfactory ability in mammals. 
     In ‘Scaling of mammalian ethmoid bones can predict olfactory organ size and performance’ (Proceedings of the Royal Society, Biological Sciences 272: 957–962, 2005), H. Pihlström, M. Fortelius, S. Hemilä, R. Forsman, and T. Reuter find that ‘[olfactory] sensitivity increases with increasing absolute organ size,’ specifically the area of the perforated portion of the cribriform plate of ethmoid. That bone forms part of the nasal fossa’s roof, and also cradles the olfactory bulb on the underside of the brain. This sieve-like area of bone transmits tendril-like soft tissue structures that are the bits of the olfactory architecture that encounter the environment.  

Ethmoid shown in pink. From Gray’s Anatomy. The cribriform portion is the thin, nearly horizontal structure between the Crista galli and the Superior Concha. Here the artist has indicated several perforations with short, almost vertical, black lines traversing the cribriform plate.

Ethmoid viewed from above. From Gray’s Anatomy.

This knowledge has allowed me to develop a single, testable hypothesis:

If the Neanderthal mid-facial skeleton evolved in tandem with carnivory, and specifically that olfactory sensitivity was significantly greater than that of modern humans, we should expect to see an absolutely larger cribriform area of ethmoid than we see in modern humans or in antecedent morphospecies.

Alas, it has become evident that comparatively little is known about the morphology of the Neanderthal  superior nasal fossa, and especially the size and morphology of the cribriform plate of ethmoid. This is a serious [you might say ‘terminal’] drawback for any investigation into the olfactory capacity of our late-Middle Pleistocene European fossil relatives. If, in truth, there is little fossil material, it will likely be because most of the ethmoid bone is extremely fragile, which you can observe in the photograph of a human ethmoid, below.

Click for photo credit.

And that’s where you come in, Dear Reader. I suspect that you or someone you know has knowledge of, or access to, fossil material that could be examined for the information needed to test my singular hypothesis. If so, I have a proposal for you to consider. Join me, Harry Potter, in this research and together we will rule over publish our findings for the edification of all. That’s a promise.
     As you can probably understand, not only do I think this idea has legs, but also that empirical support for it and its publication would likely sew up a prominent place for it in the list of really cool things about Neanderthals that everybody will thenceforth learn about and take to heart.
     Interested? 
     If so, please feel free to leave a comment if you have or know someone with information that will either support or refute my hypothesis [because after all, I’m a scientist, and however fondly I hold to my novel and elegant theories I’m well aware that I can be just wrong about stuff]. 
     Fame and fortune await you. And, if your name is Dan Lieberman, greater fame and even greater fortune will come to you. As far as I know, Dan, having published everything of value having to do with the evolution of the human head, has to date had nothing to say about this matter. If I’m wrong, someone please leave a comment disabusing me of my naive perception [and forever ruining my already feeble credibility in the wizarding world discipline!]. 

A shamelessly obsequious plug  for Dan’s book.


2 thoughts on “My Kingdom for a Neanderthal Cribriform Plate of Ethmoid!

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