Good find. After reading that article I did a little more exploration. It also gave me an excuse to dust off a paper (actually I opened the PDF) that I've had for some time that reported parthenogenesis in Burmese Pythons.Originally Posted by Vomitore
That paper can be found here
Groot T V M, Bruins D and Breeuwer J A J (2003). Molecular genetic evidence for parthenogenesis in the burmese python, Python molurus bivittatus. Heredity 90:130-135.
In addition, the news article from the original source, Nature, is extremely helpful in understanding the last quote from the yahoo article.
"The genetics of self-fertilization in lizards means that all her hatchings would have to be male."
http://www.nature.com/news/2006/0612.../061218-7.html
If your a more audio learner, you might be interested in this week's Nature Podcast. (See 21 Dec 2006)
Right click and save the mp3 to your desktop, open it with your favorite mp3 player and if you want fast-froward to the herp-core parts then go to 11:35 of the cast. The segment on the Komodo dragon findings is about 7.5 minutes long.
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If you look at the primary research article from Heredity and read it carefully and compare it to the finding related in Nature this week, you'll notice that parthenogenesis isn't just parthenogenesis. In other words, That is the mechanisms and genetic consequences of parenthogenesis in Burmese pythons is different than that of komodo dragons. It also goes to show you that there are a lot of biological mechanisms for self-fertilization and asexual reproduction.
(Get out a biobook and look at meiosis and gametogenesis, also remember for birds and reptiles the female is the heterogametic sex; Females=ZW, Males are ZZ)
The mechanism in Komodo dragons occurs by a secondary polar body fusing with the the mature ovum. The offspring of this cross are always male and are not clones of their mother. They are homozygous at ever loci however(this is why they are all male reptiles-ZZ). This reduces the genetic diversity as mention in the nature article.
In the Burmese report the exact mechanism is unknown as far as I know. But all the offspring are clones and genetically identical to their mother. However, these clones lose none of the genetic diversity (i.e. the heterozygousity of their mother--and This is why they are all female-ZW)
I can see evolutionary/survival advantages to both modes of parthenogenesis.
In Komodos, the population can expand and have members of both sexes present to allow for sexual reproduction.
In burmeses, you see no inbreeding-like effects.
PS>Both studies the one in 2003 and this recent one did a good job in ruling out sperm retention as a possibility.
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