Kiwahirsuta
Source: http://en.wikipedia.org/wiki/File:Kiwahirsuta.jpg

By Kelly

There is a creature on this great planet of ours that I dearly love. I can’t say it’s always been my favourite because it was only discovered ~8 years ago. OnCirculation readers I would like to introduce you to Kiwa Hirsuta, otherwise known to its friends as the Yeti Crab. Perhaps it’s the common name that attracts me, or the fact that they look like they are wearing little crab-sized marabou jackets. Or maybe it’s because they hail from my favourite place on Earth, the deep ocean. A study reported in the open access journal Plos One in late 2011 that just came my way describes the second species found, and some adaptive strategies that are even funkier than their jackets.

In what is possibly my favourite title so far this decade, Dancing for Food in the Deep Sea: Bacterial Farming by a New Species of Yeti Crab, describes how these deep-sea crustacea survive so far from the sun’s energy. The base of the food chain in this environment, perhaps not surprisingly, is chemosynthetic bacteria.

It turns out the bacteria live in the Yeti crab’s marabou sleeves, which the crabs can then harvest using a specialized appendage (think deep-sea salad fork). The study uses isotopic and fatty acid analyses to determine that these bacteria make up the crab’s main food source, and that they are ‘farming’ them. The reason the crabs can be seen waving their claws around (see below) is that they are providing the precise chemical environment for the bacteria to thrive i.e over the vent fluid. For a closer look, National Geographic have some amazing footage from close to the Antarctic (the T is NOT silent), or you can read the full article here.