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Re: aquatic equus?Holly Reeser (reeser@flmnh.ufl.edu)Tue, 27 Aug 1996 19:46:56 -0400
> > Holly Reeser wrote: > > > > I am currently working from fossils from Leisey Shell Pit. In broad > > strokes....if I was assuming that finding fossils in an aquatice context > > presupposes that they were themselves aquatically adapted then my Equus > > fossils must represent a period in the evolution of the horse when they > > were too aquatic since their remains were found in association with > > marine organisms deposited in a shallow embayment. Eureka it is a > > breakthrough! > > <Sarcasm mode on> > > Oh yes indeed! There is even more evidence for an aquatic past for equus: > keep in mind that horses love the water, and horses are often seen > running on the ocean beaches. (That's Morgan-esque evidence). > Cows, on the other hand, do not like the water, and are not seen > running on the ocean beaches. There you go. It's a lock. Cows evolved on > land, and horses had a past aquatic phase. > > <Sarcasm mode off> > > Seriously, > At a recent S.V.P. conference, a paleontologist from Idaho (G. McDonald) > and a co-author reported that they had evidence for an "aquatic" sloth > from the Pliocene of South America. > Their evidence for aquaticness in this animal is at odds with the so- > called "evidence" that Hardy and Morgan use to infer aquaticness in > their purported hominid ancestor. > One of the pieces of evidence that McDonald used was the depositional > environment of the site. But, more importantly, he cited a short list > of morphologic features that, in my opinion, carry more weight than the > dep.env. evidence. > Anyone who has spent ANY amount of time working with marine rocks > knows how much terrestrial material is usually incorporated in the > unit. > In my area of knowledge (Tert. marine rocks of the Pac. NW.), I > personally am aware of a gomphothere skeleton (a mastodon-like animal) > that was deposited near the very center of a large Miocene marine > embayment. I also know of many examples of dinosaur skeletons (terrestrial > creatures) that were found in the marine Bearpaw Shale of the > Western Interior. > > In my opinion, the depositional environment is the least important > piece of evidence that should be used to determine the niche of an > exinct animal. In fact, it has a strong tendency to lead one down > the wrong path. > <pb>
Exactly my point....Leisey Shell Pit's depostional environment was a
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