Only two species of little marine worm-like creatures with a ciliated line in the middle, and yet they form their own distinct phyla, Xenoturbellida. They were thought to be acoelomorpha, similar to flatworms, and yet they have no muscular pharynx, and they mesoderm is somewhat reduced, and mainly forms muscles. They have a nervous system similar to that of echinoderms, with nervous cells embedded in their skin and linked to the nervous system below, and molecular analisys seems to confirm that they are, in fact, a sister group to echinoderms. Why them this week? Because I’m currently studying all of the animal phyla at once, and I wanted one that was truly unknown and apparently insignificant.
On a side note, fuck SOPA, PIPA and the shut down of Megaupload. I’m not an american citizen, but this bullshit affects the freedom of information in all the world – it’s the nature of the internet. The good news is that no matter how hard they’ll try to regulate the web, the web “finds a way”, to put it in Jurassic Park terms. Anonymous has already counterattacked, and this certainly is just the beginning.