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Will Dunham's
WASHINGTON, Nov. 29 (Reuters) – A 4.5-meter-long prehistoric whale that sucked a prey into its mouth represents a missing piece regarding the evolution of the lynx. huge current filter Whales, scientists announced Thursday
Researchers have described Oregon's discovered fossils of a whale called Maiabalaena nesbittae, which lived 33 million years ago and possessed no teeth nor baleen, material that modern filtering whales use to filter large amounts of tiny prey out of the water for food
They called Maiabalaena, which means "mother whale", a surprising stadium. 39, an intermediate evolution between modern baleen whales and their toothed ancestors. Maiabalaena was eating fish and squid by sucking them in her mouth.
The evolutionary stages that led to modern filter giants such as the blue whale, the largest known or present animal on Earth, remained obscure. The fanon is a soft material composed of keratin, identical to the hair and nails
One of the most advanced hypotheses was that, from the early stages of their evolution, the whales possessed both teeth and baleen, before then become without teeth. The researchers indicated that Maiabalaena's position in the whale's family tree indicated that tooth loss had preceded the whalebone by several million years.
"This fossil demonstrates that tooth loss and the origin of baleen are distinct evolutionary changes, and that both the changes do not overlap," said Nick Pyenson, curator of Fossil Marine Mammals at the Museum. Natural History National of the Smithsonian Institution and author of the book "Espionage des wales."
"Maiabalaena suggests that major evolutionary changes in the way whalebone whales fed themselves, such as loss of chewing, before the innovation of filter feeding, "added Pyenson
Whales are marine mammals.The first whales emerged from terrestrial ancestors resembling wolves there are about 50 million. All the first whales had teeth.
The oldest direct dewlap trace dating back 11 million years, but scientists suspect that the first whales Baleeners appeared about 23 million years ago.
Fossils Discovered Near the Pacific Coast in Oregon Lincoln County showed that Maiabalaena had well-developed bones in the throat that served as attachment points for muscles that depressed the tongue and contributed to sucking.
"Suck feeding may seem strange to an ancestor of today's blue whales, but it is a common mode for live whales such as sperm whales and many species of dolphins," said the paleobiologist from the George Mason University, Carlos Mauricio Peredo, the museum's predoctoral fellow.
The research was published in the journal Current Biology. (Report by Will Dunham, edited by Bill Berkrot)
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