It appears that I started this blog just in time: in a paper just-out today in PLoS Biology, entitled Independently Evolving Species in Asexual Bdelloid Rotifers Fontaneto et al. describe their recent results on the "scandalous" bdelloid rotifers:"The evolution of distinct species has often been considered a property solely of sexually reproducing organisms. In fact, however, there is little evidence as to whether asexual groups do or do not diversify into species. We show that a famous group of asexual animals, the bdelloid rotifers, has diversified into distinct species broadly equivalent to those found in sexual groups. We surveyed diversity within a single clade, the genus Rotaria, from a range of habitats worldwide, using DNA sequences and measurements of jaw morphology from scanning electron microscopy. New statistical methods for the combined analysis of morphology and DNA sequence data confirmed two fundamental properties of species, namely, independent evolution and ecological divergence by natural selection. The two properties did not always coincide to define unambiguous species groups, but this finding is common in sexual groups as well. The results show that sex is not a necessary condition for speciation. The methods offer the potential for increasing our understanding of the nature of species boundaries across a wide range of organisms."In other words, these data suggest that bdelloids seem to evolve just like "normal" sexual eukaryotic species. Hmm...if it quacks like a duck...
Thanks to Coturnix for the lead. Thanks also to David Mark Welch & Matthew Meselson for the image: see Meselson's website for the legend.