I have a hard time remembering the name Aspidoscelis uniparens, because when it first broke into the limelight, it was Cnemidophorus uniparens. Sort of like how everyone continued calling Prince “Prince” even after he changed his name to a squiggle. If only he’d been known as a squiggle first when he released “Little Red Corvette”...
That there were no males in this species – a vertebrate! – was interesting enough. But what made this doubly wild was that while there was absolutely no genetic need for any other individual, these lizards, if given the opportunity, would perform pseudocopulation. That is, if you saw two lizards, they would engage in behaviour that, if you didn’t know they were both female, you would say, “They’re getting some action.” Yeah, you know what I’m talking about.
Now that is the sort of thing that impresses upon an undergraduate how little she or he knows about the natural world.
It makes sense, as so many things do, when viewed from an evolutionary point of view. If these animals evolved from a sexual species, the behaviour may lag behind the genetic changes. Sort of how like the hottest days of the year are usually a bit after the longest days of the year.
There’s a series of papers on this lizard, mainly from the lab of David Crews. He’s authored many other papers on many other species besides Aspidoscelis uniparens, I should say.
Reference
Crews D, Fitzgerald KT. 1980. "Sexual" behavior in parthenogenetic lizards (Cnemidophorus). Proceedings of the National Academy of Sciences of the United States of America 77(1): 499-502. http://www.pnas.org/content/77/1/499.short
Color photo by Manrus on Flickr. Used under a Creative Commons license.
