Christmas Island red crabs (Gecarcoidea natalis)
heading to sea
Christmas Island is home to 20 terrestrial and intertidal crabs, including coconut crabs (a personal favorite: I’ve seen these guys in the Solomon Islands) and red crabs. The latter are famous for their massive march to the sea from their jungle home:
(I strongly encourage you to watch all the National Geographic videos on the red crab migration [millions of crab babies!!], but I’ll warn you now: you will come to hate yellow crazy ants!)
SO MANY BABIES!
Red crabs undergo an incredible physiological change when embarking on their journey: they have to get their muscles from couch-potato to marathon-runner, which involves changes in their gene expression (rather than an 18 week training program. Lucky!). Scientists from the University of Bristol just published an article on red crab leg muscles, and it is covered quite splendidly here.
I’ll leave you with my take on a Christmas Island Christmas tree:
Red crab reading:Postel, U., F. Thompson, G. Barker, M. Viney, and S. Morris. 2010. Migration-related changes in gene expression in leg muscle of the Christmas Island red crab Gecarcoidea natalis: seasonal preparation for long-distance walking. Journal of Experimental Biology 213: 1740-1750.