Remarkable convergent evolution in specialized parasitic Thecostraca (Crustacea)

Yet another case of *remarkable* convergence at the evolutionary level. At what point is there enough evidence to overturn the notion that evolution follows random trajectories.

"Our analyses indicate a convergent evolution of the very similar and highly reduced slug-shaped stages found during metamorphosis of both the Rhizocephala and the Facetotecta. This provides a remarkable case of convergent evolution and implies that the advanced endoparasitic mode of life known from the Rhizocephala and strongly indicated for the Facetotecta had no common origin."

Shaking up the theory of evolution

I've argued for quite some time that current gradualistic evolutionary theory does not square with the fossil record. The fossil record is categorized by long periods of stasis followed by brief periods of the introduction of new species.

This article describes a new theory (which isn't really new as its been talked about in the past) that argues that junk DNA is the primary impetus for speciation.

How crazy is that? Junk DNA once was the tool of the naturalist -- who argued that it was inconsistent with intelligent agency. Meanwhile it turns out that it may be a central component into the origin of species.

"In a co-authored report, due to be published in the prestigious BioEssays journal, the researchers argue that transposable elements (TEs) – or what is colloquially termed jumping genes, selfish or junk DNA, have a critical role in ensuring the survival of biological lineages.

Without this DNA junk, a species is effectively frozen and faces eventual extinction."