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[QUOTE]Originally posted by DD'eDeN: [QB] Elephant evolution http://news.bbc.co.uk/2/hi/science/nature/7347284.stm Note: Moetherium - 37ma semi-aquatic ancestor of elephantidae, somewhat similar to manatee (but with rear limbs), distinct from Hyrax & elephant shrew (much larger). It consumed river & swamp plants. - - - John Hawks blogs about new DNA elephant study, which finds that the EurAsian straight tusked elephant descended from African Forest Elephant, and that the Forest elephant hybred with mammoths and mastodons. "All four of the P. antiquus mitochondrial lineages are on the same branch as living forest elephants, and in fact some forest elephants have mtDNA genomes that are closer to P. antiquus than to some other forest elephants. In other words, the mitochondrial genomes of P. antiquus fall within the variation of L. cyclotis." "In humans, mtDNA is markedly less diverse than most parts of the nuclear genome, and mtDNA types occur across wide geographic areas. Elephants are the opposite. Their mitochondrial DNA exhibits substantially greater variation among populations than the average for the nuclear genome, because female elephants very rarely transfer between groups. Most gene flow in elephants is male-mediated, and male elephants sometimes disperse over very long distances." Note: Elephant herds with females and young are always led by matriarchs (as are bison). "What they found was that P. antiquus mitochondrial genomes are not related to Elephas at all; they’re related to forest elephants: Surprisingly, P. antiquus did not cluster with E. maximus, as hypothesized from morphological analyses. Instead, it fell within the mito-genetic diversity of extant L. cyclotis, with very high statistical support (Figure 2). The four straight-tusked elephants did not cluster together within this mitochondrial clade, but formed two separate lineages that share a common ancestor with an extant L. cyclotis lineage 0.7–1.6 Ma (NN) and 1.5–3.0 Ma (WE) ago, respectively. "That’s not a small difference. [b]Living Asian and African elephants came from a common ancestral population more than 6 million years ago, during the Late Miocene. They are about as different from each other genetically as humans and chimpanzees. The fossil story was just wrong[/b]–and it’s as big a difference as misidentifying a Neanderthal as a fossil chimpanzee." A widespread extinct species of elephant, which on morphological grounds was interpreted as an Asian elephant relative, is actually related to forest elephants within Africa. Forest elephants today are a relative island species in central Africa, surrounded by savanna elephants. So from today’s standpoint, forest elephants look like a geographic and phylogenetic relict of a much more diverse lineage that once existed." Note: Dr. Hawks unfortunately confuses today's Ituri Rainforest elephants as a "relict" population of EurAsian straight tusked elephants. Actually [b]the Ituri rainforest is the SOURCE population of both; as it is also the source of long-necked open plains giraffes from Ituri Okapi and tall AMHs open plains people from Ituri Pygmies[/b]. Principles of Parsimony & Continuity should not be ignored in accurate scientific explanation. - - - http://news.bbc.co.uk/2/hi/science/nature/6913934.stm [b]"The [2007 DNA] tree has the African elephant diverging from both the Asian elephant and the mammoth about 7.6 million years ago. Then, at 6.7 million years ago, the Asian elephant and the mammoth also go their separate ways. That took place in Africa in the same place where humans, chimps and gorillas diverged."[/b] Note: Elephants split at same place and same time as hominins from apes, Congo. Human comparison "The cool thing about the mastodon is that we know pretty exactly from the fossil record when it diverged from the elephant and the mammoth," said Dr Michael Hofreiter of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and one of the lead researchers. "So using that time point and the genetic data, we could date when the African elephant, Asian elephant and mammoth diverged from each other," Dr Hofreiter explained. "That took place in Africa in the same place where humans, chimps and gorillas diverged." The fact that it is now judged that the elephants went their separate ways in the same place and at about the same time we humans diverged from our ape brethren may of course be a coincidence. Or, as Dr Hofreiter suggests, there may be a common environmental or climatic event which set both elephants and humans on their eventual evolutionary course. " - - - [Errata: Straight tusked elephants hybred with mammoths and Asian elephants, not mastodons.] - - - Elephant hybridization "Hybridization has already been found to be widespread among the varieties of mammoths, and it continues to occur between savanna and forest elephants despite what appears to be a multi-million year separation. We might expect the same of other extinct elephant species. When Eleftheria Palkopoulou presented on some of these data at a conference in 2016, she did talk about hybridization. Ewen Callaway reported on that conference presentation at the time: “Elephant history rewritten by ancient genomes”. http://www.nature.com/news/elephant-history-rewritten-by-ancient-genomes-1.20622 "Palkopoulou and her colleagues also revealed the genomes of other animals, including four woolly mammoths (Mammuthus primigenius) and, for the first time, the whole-genome sequences of a Columbian mammoth (Mammuthus columbi) from North America and two North American mastodons (Mammut americanum). The researchers found evidence that many of the different elephant and mammoth species had interbred. Straight-tusked elephants mated with both Asian elephants and woolly mammoths. And African savannah and forest elephants, who are known to interbreed today — hybrids of the two species live in some parts of the Democratic Republic of Congo and elsewhere — also seem to have interbred in the distant past. Palkopoulou hopes to work out when these interbreeding episodes happened." [/QB][/QUOTE]
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