Remains may be an evolutionary relic.Fossils recently found in southwestern China may be of a lineage that originated long before the Cambrian explosion Cambrian Explosion n. The rapid diversification of multicellular animal life around the beginning of the Cambrian Period, resulting in the appearance of almost all modern animal phyla. of biodiversity, when most major groups of animals first Animals First was a New Zealand political party dedicated to animal rights and animal welfare. In the 1996 elections, it won 0.17% of the vote, putting it in twelfth place. In the 1999 elections, it declined slightly, winning 0.16% of the vote (fourteenth place). appeared in the fossil record. The frondlike animals were up to 7.5 centimeters long and anchored themselves to the seafloor with a hollow stalk, says Simon Conway Morris Simon Conway Morris FRS is a British paleontologist. He was born in 1951 and brought up in London, England.[1] He made his reputation with a very detailed and careful study of the Burgess Shale fossils, an exploit celebrated in Stephen Jay Gould's Wonderful Life , a paleontologist at the University of Cambridge in England. The rocks bearing the fossils were deposited on an ocean bottom about 520 million years ago during the Cambrian period Cambrian period [Lat. Cambria=Wales], first period of the Paleozoic geologic era (see Geologic Timescale, table) extending from approximately 570 to 505 million years ago. . The fine-grained sediments that covered the organisms preserved details of the animals that haven't been seen in other fossils. Such features include a network of channels that ran between neighboring neigh·bor n. 1. One who lives near or next to another. 2. A person, place, or thing adjacent to or located near another. 3. A fellow human. 4. Used as a form of familiar address. v. branches of the frond. "These [animals] are strikingly similar to older organisms," says Conway Morris. Creatures with multiple frondlike structures lived at least 20 million years earlier, during the Ediacaran period, the interval that immediately preceded the Cambrian. Conway Morris and his colleagues suggest in the May 5 Science that the Cambrian fronds are members of a lineage that survived the Ediacaran period, although they mention other potential scenarios.--S.P. |
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