Wednesday, June 06, 2007

Lesbian Clone Lizards..

.. is what Libby and I call Cnemidiphorus neomexicanus and her relatives. We are not being rude, but literal. Neomexicanus is described on page 319 of the newest edition of the Peterson Guide to Western Reptiles and Amphibians as being "ALL FEMALE".

Patrick explains:

"For example, believe it or not, there are no male Whiptail Lizards; all Whiptail Lizards are female, and all are natural clones.

"What happens here is that two female Whiptail Lizards will engage in "pseudocopulation" in which one female gets on top of another and grinds away like a male, and then they reverse their respective roles. This activity stimulates egg production in both lizards, which then lay fertile eggs."

From an evolutionary viewpoint this can be a problem-- virgin births= parthenogenesis= clones= no variation. From a practical point of view, at least in this environment, it appears to mean little-- I could go into the side yard and find one in a minute flat. Maybe I'll get a photo later.


Peter said...

Yeah, but do the lizards wear flannel shirts and listen to the Indigo Girls ...?

Jonathan Hanson said...

dysqiFrom a practical point of view, it is thought that parthenogenesis can be advantageous to a species trying to rapidly colonize a new kind of habitat. If you can skip the flowers/candy/dating part of reproduction and go straight to producing young, you're ahead of the game . . . for as long as the stability of the habitat lasts. One theory regarding parthenogenesis in whiptails is that it developed concurrently with the introduction of cattle. The habitat produced by domestic grazers proved ideal for whiptails, and they found a way to colonize it as quickly as the cattle could produce it. Not sure if this has been tested.

Oh, and . . . they changed the genus! We can't call them nemmies anymore. Harumph.