Re: aquatic equus?

Phillip Bigelow (bh162@scn.org)
Mon, 26 Aug 1996 14:30:18 -0700

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>