Jellyfish of the Day #5: Comb Jellyfish
"Geez John, why do you like jellyfish so much?" Uh, they are the superlative species in practically EVERY category! Case in point: Ctenophores (pronounced "TINA-fours") - commonly called "comb jellies.” While they are not the largest animals (like Lion’s Mane Jellyfish) or the deadliest animals (like Box Jellyfish), comb jellies recently dethroned sea sponges as the OLDEST known animal. In December of 2013, DNA sequencing proved that sponges actually evolved from comb jellies - not the other way around - which means that, genealogical-family-tree-wise, EVERY ANIMAL evolved from comb jellyfish.
I remember being a kid, playing in the Sound (the “Long Island” one, not the “South Puget” one) and seeing these clear little anomalies zoom around underwater with seemingly zero effort. That’s because comb jellies don’t undulate, but use rows of tiny iridescent hairs called cilia (which look like rainbowy combs, hence the name) to flutter through the sea like shimmering aliens. And they kind of are aliens. For a single phylum of animal, comb jellies have the most widely varying body shapes, and each newly discovered species looks and functions nothing like last (see pix). They are the only things larger than cells that use cilia for locomotion, and anatomically, are just stomachs that swim - comb jellies can eat things much larger than themselves by simply stretching themselves all the away around their prey, and then slowly absorbing it into their transparent bodies. There are hundreds of species in the Ctenophora phylum, but I’m lumping them into one post because they are such a remote branch of the jellyfish tree - albeit a beautifully bizarre branch of said tree.
Besides, I’ve been sending a lot of nasty jellyfish, and thought I’d introduce some harmless, pretty ones before I showed you THE MOST DESTRUCTIVE JELLYFISH THAT EVER LIVED later this week. See? Superlatives.
NatGeo video of comb jellies swimming and eating - Wow! Such elegant! Very colors! Many science! http://www.youtube.com/watch?v=39qe0EajbIA