Rapidly Evolving Cushion Stars
A small group of the short-legged sea stars (known as “cushion stars”) have rapidly evolved, and unlike their cousins, they don’t need a mate to reproduce.
Their evolution into live-bearing hermaphrodites is one of the fastest known examples of speciation among marine animals, say the authors of a study published online today
The researchers analyzed DNA from the tissue of nearly 400 sea stars, half belonging to the original and still existing species, Cryptasterina pentagona, and half from the new species, C. hystera. By comparing DNA sequences, they have inferred that C. hystera evolved their ability to mate with themselves between 1,000 and 22,000 years ago.
For scientists, complex beings like these evolving in the space of a few thousand years is unusual and extremely rapid. But from a catastrophist angle it isn’t surprising at all. Punctuated equilibrium is already an accepted theory. But few scientists (yet) would entertain the idea of evolution in the space of a generation, 12,000 years ago. It is possible, we just need an event that sends us a massive dose of cosmic rays.
