Re: Ancestors of armadillos
David Froehlich (eohippus@moe.cc.utexas.edu)
Thu, 19 Oct 1995 19:51:12 -0500
On 19 Oct 1995, donald e. tyler wrote:
>
> Reportedly the diploid chromosome
> number is 62 of the soft-tailed
> armadillo, 60 for the hairy
> armadillo, 64 for the nine-banded
> armadillo, and 58 for the six
> banded armadillo. Is one of these
> the ancestor of the others, or do
> they all have a common ancestor.
> If there is any evidence of
> mental retardation or deformaties
> associated with any of these
> species suggesting loss of chromosomes
> I would appreciate the information.
> Any ideas as to the number of
> chromosomes common ancestors had
> and what their physical characteristics
> might be?
> --
I am not sure of the purpose of these posts on chromosomal number. As in
the previous post, to make any sort of attempt to make an informed guess
(and that is probably what it would be) you would need a phylogeny of the
armadillos and since I work on horses I have no real knowledge of
armadillo systematics. However, there is a long fossil record of
armadillos in South America (they are relatively recent immigrants to
North America (c. 5mya). I do know that there were close relatives to
the nine-banded armadillo (Dasypus novemcinctus) in Texas in the
Pleistocene (Dasypus bellus). D. bellus is actually about 50% larger
than D. novemcinctus and may be an ancestor (big set of assumptions
here). D. novemcinctus actually is a very recent immigrant into the US.
There is a series of Pleistocene records in Northern Mexico but no D
novemcinctus is known in Texas until 1880. The Florida population is
actually human introduced (a side show somewhere in northern Florida
about 1930 led to their introduction). Kind of interesting that the
state roadkill of Texas was only introduced recently.
(The above is totally off the subject of paleoanthro and you might try
asking your questions either in sci.bio.paleontology or in
sci.bio.systematics)
David J. Froehlich Phone: 512-471-6088
Vertebrate Paleontology Laboratory Fax: 512-471-5973
J.J. Pickle Research Campus
The University of Texas, Austin, Texas 78712
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