Missing link dating
"The number of extinct side-branches is much larger than the number of true genealogical connections in the fossil record, and so when we find a fossil, we don't assume it's an ancestor of anything we interpret it as a sister group of some things."While all modern species have followed different evolutionary paths, humans share a common ancestor with some primates, such as the African ape.
For example, the hominid biological family branch includes humans, chimpanzees, gorillas and their extinct ancestors, while hominins include those species after the human lineage split from that of chimpanzees."The notion of the 'missing link' dates from the early 20th century, when it was thought that human ancestors formed a sort of single chain receding into the remotest past," said paleoanthropologist Ian Tattersall at the American Museum of Natural History in New York.
More recently, fossils of a "bird-dinosaur" were labeled as a missing link by National Geographic in 1999, but were later discovered to be the deliberately combined body of an early toothed bird with the tail of a dinosaur.
The discovery of the 95%-complete ‘lemur monkey’ Now that “95%-complete lemur monkey” is one of the few factual statements in the various press releases about the new fossil named Ida announced last May 20, 2009.
At 2 million years old, they show a mix of features, some similar to the ape-like australopithecines, others more like our genus, Homo. sediba was becoming human, and that the Homo genus first evolved in South Africa, not east Africa as is generally thought. sediba was becoming human and is evidence that we evolved in South Africa” But a new analysis suggests A. “I think there are two different hominin genera represented at Malapa,” says Ella Been at Tel Aviv University in Israel. We can’t yet tell if the australopithecine remains are distinct enough to call them a new species, Been says.
Been studies the spinal columns of ancient hominins, so she was curious when a paper was published last year focusing on the spine of A. There are fragments from two skeletons at Malapa, a juvenile male and an adult female.
"On the one hand, it's a truism we can never recover every individual that contributed genetically to today's species, so we should expect 'links' to be missing.
sediba really was a transitional species between Australopithecus and Homo.
“A central tenet of evolutionary theory is that variation within taxa becomes variation between taxa as species diverge,” he says. sediba had an Australopithecus-like spine and Homo-like jaw, while another had a Homo-like spine and Australopithecus-like jaw. sediba vertebrae that might explain the differences Been found.
They presented their findings at a meeting of the Paleoanthropology Society in Calgary, Canada, this week. sediba‘s discoverer, Lee Berger of the University of Witwatersrand in South Africa, doesn’t agree. erectus, but he says vertebrae grow taller throughout childhood. sediba had grown up, his vertebrae may have become more Australopithecus-like. Fossils of other australopithecine children had tall vertebrae, she says.
For one thing, he says the positioning of the adult skeleton’s bones in the ground makes it likely they came from a single individual. Regardless, Berger says that Been and Rak’s observations make sense if A.