The Miocene Pinniped Allodesmus - A Four Part Review On My Blog

[Boesse]

Hey All,

For those of you with an interest in Sharktooth Hill or fossil marine mammals, here's a four part post on the pinniped Allodesmus from my blog "The Coastal Paleontologist".

The best known fossil pinniped, part 1: a review of research and taxonomy of the Miocene pinniped Allodesmus

The best known fossil pinniped, part 2: How many species (...and genera) are there of Allodesmus, anyway?

The best known fossil pinniped, part 3: life habits, paleoecology, and biogeography of Allodesmus

The best known fossil pinniped, part 4:Phylogenetic relationships and evolution of Allodesmus, and future directions

Edited June 11, 2014 by Boesse

[Auspex]

Good work, Bobby; Thanks!

[siteseer]

Bobby,

That is a great recap of the history of scientific understanding of Allodesmus.

If the type locality of A. kernensis is uncertain, wouldn't that be grounds alone to render the species invalid?

It does strain credibility that the first described jaw represents one species, the best skeleton belongs to another species, and all the other known remains should be referred to a third species, all specimens having been collected from the same thin bonebed (maybe 8 inches deep on average) representing less (perhaps much less) than 700,000 years of deposition. I've always wondered why with all the richness the STH Bonebed offers, relatively little has been published on it since the 1930's - no published review of the sharks (though various faunal lists have been floating around for decades), no review of the bony fishes, no review of the whales, etc, though that recent article on the known land mammals (Prothero et al., 2008) was a nice surprise. Anyone interested in STH pretty much has to piece together reviews from various sources, formal and otherwise. I guess some of those LACM workers just never get around to it (although Bruce Welton seems to be making up for lost time) leaving it wide open it to your generation.

I think that photo of the girls with the Allodesmus "skeleton" is actually the result of someone having bought a Mary Odano (Valley Anatomical) cast of a skeleton (one of the two collected by Bob Ernst). Someone then tried to make a display showing what seemed like a natural death pose. I guess you would call it an artwork. I've seen it for sale online.

Jess

Hey All,

For those of you with an interest in Sharktooth Hill or fossil marine mammals, here's a four part post on the pinniped Allodesmus from my blog "The Coastal Paleontologist".

The best known fossil pinniped, part 1: a review of research and taxonomy of the Miocene pinniped Allodesmus

The best known fossil pinniped, part 2: How many species (...and genera) are there of Allodesmus, anyway?

The best known fossil pinniped, part 3: life habits, paleoecology, and biogeography of Allodesmus

The best known fossil pinniped, part 4:Phylogenetic relationships and evolution of Allodesmus, and future directions

Edited June 13, 2014 by siteseer

[Boesse]

Comments below in bold:

Bobby,

That is a great recap of the history of scientific understanding of Allodesmus.

If the type locality of A. kernensis is uncertain, wouldn't that be grounds alone to render the species invalid?

Nope. All a type specimen needs to do is bear a name; the type specimen can even be a plaster cast according to ICZN rules, but that is obviously really unfavorable. Just because the locality of the specimen is uncertain doesn't mean it's invalid. Also: taxonomic validity ONLY means whether or not the name is preoccupied: an invalid name is one that has already been used.

It does strain credibility that the first described jaw represents one species, the best skeleton belongs to another species, and all the other known remains should be referred to a third species, all specimens having been collected from the same thin bonebed (maybe 8 inches deep on average) representing less (perhaps much less) than 700,000 years of deposition. I've always wondered why with all the richness the STH Bonebed offers, relatively little has been published on it since the 1930's - no published review of the sharks (though various faunal lists have been floating around for decades), no review of the bony fishes, no review of the whales, etc, though that recent article on the known land mammals (Prothero et al., 2008) was a nice surprise. Anyone interested in STH, pretty much has to piece together reviews from various sources, formal and otherwise. I guess some of those LACM workers just never get around to it (although Bruce Welton seems to be making up for lost time) leaving it wide open it to your generation.

Yup, Allodesmus is terribly oversplit. I think the reasoning behind designating three separate species defies credulity.

Honestly, the reason that so little research on Sharktooth Hill marine vertebrates has been finished is because fossil specimens from Sharktooth Hill have been "claimed" but the work has never been finished. That's really all I can say without breaking professional tact. That being said, there is new blood getting involved, and Bruce Welton has certainly been making progress on west coast fossil sharks, so that is something. It's not just a problem with Sharktooth Hill: it's a problem with west coast marine vertebrate paleo in general, and simply put, there are way way too many fossils and too few researchers. In order to get 90% of the west coast marine vertebrate fossil record published in the next two decades, we'd need to multiply the number of us working on these fossils by ten, at a minimum. That all being said, there are a number of fresh faces, and my energetic and very productive colleague Jorge Velez-Juarbe has just been appointed as the new Curator of Marine Mammals at LACM (yes, that's fossil and modern). Also, for west coast marine vertebrates, 2011 and 2013 have both been record setting years in terms of the sheer number of papers published on the subject. We're at a "second renaissance" in west coast marine vertebrate paleontology (the first renaissance being the 1970's and 80's). I wrote a bit about it here: http://coastalpaleo.blogspot.co.nz/2013/10/trends-in-publishing-for-west-coast.html

and here: http://coastalpaleo.blogspot.co.nz/2014/04/update-to-research-trends-1960-2014.html

I think that photo of the girls with the Allodesmus "skeleton" is actually the result of someone having bought a Mary Odano (Valley Anatomical) cast of a skeleton (one of the two collected by Bob Ernst). Someone then tried to make a display showing what seemed like a natural death pose. I guess you would call it an artwork. I've seen it for sale online.

Yup, that's basically what I thought as well.