Scientists Describe Ancient Bag-Like Sea Creatures From China
Scientists have described a new kind of sea creature in what’s now central China. It lived 540 million years ago, and the tiny, baggy organism could occupy a peripheral spot on our own evolutionary tree.
(From NPR / By Rae Ellen Bichell)– When scientists like Simon Conway Morris discover a new animal, they get to name it. He and his colleagues in China don’t seem to give compliments where they aren’t deserved.
“We arrived at the word Saccorhytus, which basically means a wrinkled bag,” says Conway Morris, a paleobiologist at the University of Cambridge in the U.K.
Actually, this thing is a lot uglier than a wrinkled bag. It’s basically a giant gaping mouth with spikes and some extra holes — probably for oozing waste.
“Doesn’t sound too appetizing, does it?” says Conway Morris.
Fortunately, it was no bigger than a grain of rice.
Morris and his colleagues in China and Germany announced the these ancient sand-dwellers (they found 45 of them) Monday in the journal Nature.
He says the animals likely lived about 540 million years ago, “slithering or clambering” in sediment in shallow seas.
“It has a very small body. It doesn’t have a tail. It does not appear to have eyes,” says Conway Morris. And it doesn’t appear to have an anus, either, though its pleated, expandable mouth sure did look like one.
It sounds primitive, but compared to other life in that era, this little blob of an animal was on the cutting edge. This was a time in Earth’s history when sea pens and mats of algae were about the most exciting things around.
“What we have here is an animal which we would suggest is in fact the earliest known deuterostome,” he says. Deuterostomes are a huge group of organisms that, over the next millions of years would come to include starfish, sea squirts and anything with a spine, including humans. (Interestingly, “deuterostome” is Greek for “second mouth.” That’s either a polite euphemism, or a reference to the fact that now, everything in this group — us included — develops an anus first and then a mouth after that.)