Caitlin Stier, video intern
Sea urchins start life as freewheeling larvae, only to undergo a dramatic metamorphosis that turns them into bottom-dwellers. This video -?captured by Christian Sardet and a team from Tara Oceans Expedition and the Oceanological Observatory of Villefranche-sur-Mer in France - illustrates the transformation, which is usually barely visible to the naked eye, in one episode of its Plankton Chronicles series.
After fertilization, a round urchin embryo hollows out, acquiring a gut that allows it to suck in food particles and turn into a spindly, iridescent larva. Inside its calcium armour, which looks like a miniature Eiffel tower, a spiny baby urchin develops. As it grows, it eventually digests its mother and is set free.
The urchin's body looks completely different before and after its metamorphosis: the initially bilaterally symmetrical larva becomes a radially symmetrical adult. Many marine animals go through a similar transformations, which could be the key to the evolutionary radiation that occurred more than half a billion years ago, giving rise to the entire animal kingdom.
To find out more about how metamorphosis could have driven evolution, you can read our full-length feature here.
If you enjoyed this video, check out this psychedelic jellyfish as it dances for its dinner.
monet claude monet mc hammer queen latifah smoke norah jones matthew fox
No comments:
Post a Comment