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Re: Parthenogenesis in vertebrates



--- "T. Michael Keesey" <keesey@gmail.com> wrote:

 I'd heard many times of squamates that can reproduce
> parthenogenetically, but which birds can? Can any
> non-squamate
> sauropsids (turtles, crocodylians, tuataras)?

++++++++++++++++++++++++++++++++

Turkeys can. There are probably a few other birds too,
but that's the only species that comes to mind. I'm
not sure of parthenogenic development in turtles,
crocs, or tuataras, but then, they take longer to
reproduce than most squamates, so maybe we just
haven't lucked out and found one yet.

___________________________________



> Is it males being heterozygous that prevents mammals
> from reproducing
> parthenogenetically?
> -- 
> Mike Keesey

+++++++++++++++++++++++++++++++++++++++++++++++++

I don't see why. Heterozygosity is well represented
among squamates and birds too, and it doesn't stop
them from being parthenogenic. Having all the
offspring be female could pose a problem for genetic
variability, but that's about it. Even then I can't
see that being enough of a problem to remove this
trait from mammals. Just look at the infamous
parthenogens in the genus/genera
_Cnemidophorous/Aspidoscelis_ (confusing lot). Being
polyploids has allowed them to bypass the whole
parthenogens = males scenario that is default for
reptiles and birds. In this case, it appears that
there was selection for a less variable means of
parthenogenesis.

Jason



"I am impressed by the fact that we know less about many modern [reptile] types 
than we do of many fossil groups." - Alfred S. Romer


       
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