London - Arabstoday
Flowerlike façades can be deceptive. Dense clusters of stalked creatures, rooted in the muddy bottoms of shallow seas some 500 million years ago, would have called to mind a submerged bed of tulips as they swayed gently with the passing waves. But Canadian paleontologists now know these bizarre creatures were actually animals, like none the world has ever known. Close inspection revealed that the bulbous, cup-like structure atop each stem, called a calyx, enclosed a unique filter-feeding system and gut. Notably, the animal’s anus happens to be located in precisely the spot you would position your nose for a sniff, were it actually a tulip. “This feeding system appears to be unique among animals,\" University of Toronto paleontologist Lorna O’Brien said in a press release. \"We do not know where it fits in relation to other organisms.\" O\'Brien and her supervisor, associate professor Jean-Bernard Caron, curator of invertebrate paleontology at the Royal Ontario Museum, reported their findings in this month\'s issue of the journal PLoS ONE. The pair made their discovery after extensive study of 1,133 fossil specimens of the tulip-ish animals, officially named Siphusauctum gregarium, which they found entombed in an unusual outcrop of the famous Burgess Shale in the Canadian Rockies. Recent advances have linked many bizarre Burgess Shale animals as primitive members of many animal groups that are found today, but Siphusauctum defies this trend. O’Brien and Caron think the animal fed by filtering particles from water, which it pumped into its calyx through six small holes. The water then passed by comblike structures that captured the food, which was digested in a large stomach. These stalked animals lived in gregarious clusters of dozens of individuals and died when a massive mudflow buried them alive. Paleontologists from the Royal Ontario Museum then extracted slabs of the fossilized mud from a quarry (below) in Yoho National Park, British Columbia, which is protected under the larger Rocky Mountain Parks UNESCO World Heritage site.