Missing link dating
When Been shared her findings with Yoel Rak, also at Tel Aviv University, she found an ally.“He sees the same in the [lower jawbone]: an australopithecine and an early Homo,” says Been.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.
"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.
"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.
Also known as Turkana Boy, this is a 1.5-million-year-old skeleton of Homo erectus, a widespread species that may be our direct ancestor.
Its vertebrae, like ours, are much wider than they are tall.