ALL-MALE ASEXUALITY

I found this while I was I researching Asian Clam,
after I found 2mm offspring in my pond.

Don't ask me to explain this.

ALL-MALE ASEXUALITY


Abstract
Androgenesis is a rare form of asexual male reproduction found in disparate taxa across the Tree of Life. Phylogenetic analyses of mitochondrial genes suggest that androgenesis has arisen repeatedly in the Asian clam genus Corbicula. Two of these androgenetic species have been introduced to North America. Multiple lines of genetic evidence suggest that although nuclear recombination between these two species is rare, mitochondrial genome capture is a frequent consequence of androgenetic parasitism of heterospecific eggs. Egg parasitism may also rarely result in partial nuclear genome capture between closely related species of Corbicula, which provides a mechanism for the otherwise clonal species to avoid the deleterious effects of asexuality. Egg parasitism among congeners may explain why androgenesis has been maintained in Corbicula after fixation and has not yet led to population extinction. This mechanism also provides an explanation for the apparent multiple origins of androgenesis in Corbicula as seen on the mitochondrial DNA phylogeny. We suggest that a single androgenetic lineage may have repeatedly captured mitochondrial genomes (as well as portions of nuclear genomes) from various sexual species, resulting in several distinct androgenetic species with distantly related mtDNA genomes and divergent morphologies.

Shannon M. Hedtke,1,2 Kathrin Stanger-Hall,1,3,4 Robert J. Baker,5,6,7 and David M. Hillis,1,8,9
1 Section of Integrative Biology, University of Texas, Austin, Austin, Texas 78712
2 E-mail: s.hedtke@mail.utexas.edu
4 E-mail: ksh@uga.edu
5 Department of Biological Sciences, Texas Tech University, Lubbock, Texas 79409
6 Natural Science Research Laboratory, Museum of Texas Tech University, Lubbock, Texas 79409
7 E-mail: robert.baker@ttu.edu
8 Center for Computational Biology, University of Texas, Austin, Austin, Texas 78712
9 E-mail: dhillis@mail.utexas.edu

Edited by PhilipKukulski, 26 August 2009 - 01:20 PM.

Thanks Phil, I've never encountered androgenesis before, that's truly bizarre. And it has the extra bonus of capturing mitochondrial genomes!

Woah! Now that's the stuff movies are made of! Quick - somebody call Dustin Hoffman!