No Sex Required By Edyta Zielinska | November 19, 2012
An all-female species, distantly related to flatworms, steals all of genetic material it needs to diversify its genome.
Excerpt: “Although it’s unclear how the microscopic organisms acquire the foreign DNA, it appears that they adopt many of the functions encoded within.”
My comment: From Kohl (2012) : “Among different bacterial species existing in similar environments, DNA uptake (Palchevskiy & Finkel, 2009) appears to have epigenetically ‘fed’ interspecies methylation and speciation via conjugation (Fall et al., 2007; Finkel & Kolter, 2001; Friso & Choi, 2002). This indicates that reproduction began with an active nutrient uptake mechanism in heterospecifics and that the mechanism evolved to become symbiogenesis in the conspecifics of asexual organisms (Margulis, 1998).”
If, acquisition of foreign DNA is not a receptor-mediated event consistent with nutrient chemical uptake in other species (referenced above), how could asexual reproduction be controlled by the epigenetic effects of nutrient chemicals and pheromones. That control is required in all species (to avoid out-reproducing the nutrient chemical supply in the ecological niche required for social niche construction)?
Do the molecular mechanisms in rotifers vary from those known to be required for adaptive evolution of the neurogenic and socio-cognitive niches that enable organisms with neurons and a central nervous system to find food and and to distinguish it from their conspecifics. Clearly, conspecifics would probably not appreciate being ingested any more than heterospecifics appreciate being eaten to support the nutrient chemical needs of other species that metabolize the heterospecific DNA to pheromones that ensure survival of the fittest in species from microbes to man. But that’s “Nature, red in tooth and claw.” — Lord Tennyson, even in microbial species with no teeth and no claws. Isn’t it?
What’s unclear about how the microscopic organisms acquire the foreign DNA? Did they find eating their heterospecifics to be distasteful? Other species express de novo receptors for chemicals that appear to determine whether or not they eat their neighbors. If rotifers don’t, is there a model for that?