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    KNM-ER Updated: Pleistocene Fossils Shed New Light On Early Human Evolution
    By News Staff | August 8th 2012 04:00 PM | 8 comments | Print | E-mail | Track Comments
    A face, a remarkably complete lower jaw, and part of a second lower jaw are exciting new fossils discovered east of Lake Turkana which confirm that there were two additional species of our genus living alongside our direct human ancestral species, Homo erectus, almost two million years ago.

    The finds were uncovered between 2007 and 2009 by the Koobi Fora Research Project (KFRP), led by Meave and Louise Leakey. 

    Four decades ago, the KFRP discovered the fossil known as KNM-ER 1470 (or "1470" for short). The skull, readily distinguished by its large brain size and long flat face, ignited a debate about just how many different species of early Homo lived alongside Homo erectus during the Pleistocene epoch. 1470's unusual morphology was attributed by some scientists to sexual differences and natural degrees of variation within a single species, whereas others interpreted the fossil as evidence of a separate species.



    The KNM-ER 1470 cranium, discovered in 1972, combined with the new lower jaw fossil KNM-ER 60000; both are thought to belong to the same species. The lower jaw is shown as a photographic reconstruction, and the cranium is based on a computed tomography scan. Credit: © Photo by Fred Spoor

    The debate has endured for two reasons: First, comparisons with other fossils have been limited due to the fact that 1470's remains do not include its teeth or lower jaw; second, no other fossil skull has mirrored 1470's flat and long face, leaving in doubt just how representative those characteristics are. The new fossils address both issues. 

    "For the past 40 years we have looked long and hard in the vast expanse of sediments around Lake Turkana for fossils that confirm the unique features of 1470's face and show us what its teeth and lower jaw would have looked like," says Meave Leakey, co-leader of the KFRP and a National Geographic Explorer-in-Residence. "At last we have some answers."


    Found within a radius of just over 10 km from 1470's location, the three new fossils are dated between 1.78 million and 1.95 million years old. The face KNM-ER 62000, discovered by field crew member Elgite Lokorimudang in 2008, is very similar to that of 1470, showing that the latter is not a single "odd one out" individual.

    Moreover, the face's well-preserved upper jaw has almost all of its cheek teeth still in place, which for the first time makes it possible to infer the type of lower jaw that would have fitted 1470. A particularly good match can be found in the other two new fossils, the lower jaw KNM-ER 60000, found by Cyprian Nyete in 2009, and part of another lower jaw, KNM-ER 62003, found by Robert Moru in 2007. KNM-ER 60000 stands out as the most complete lower jaw of an early member of the genus Homo yet discovered.

    "Combined, the three new fossils give a much clearer picture of what 1470 looked like," says Fred Spoor, leader of the scientific analyses. "As a result, it is now clear that two species of early Homo lived alongside Homo erectus. The new fossils will greatly help in unraveling how our branch of human evolution first emerged and flourished almost two million years ago."


    The team working on the new finds included Christopher Kiarie (TBI), who carried out the laboratory preparation of the fossils, Craig Feibel (Rutgers University), who studied the age of the fossils, and Susan Antón (New York University), Christopher Dean (UCL, University College London), Meave and Louise Leakey (TBI, Kenya; and Stony Brook University, New York) and Fred Spoor (Max Planck Institute for Evolutionary Anthropology, Leipzig and UCL), who analyzed the fossils. The National Geographic Society funded the fieldwork, the Leakey Foundation funded geological studies, and the Max Planck Society supported laboratory work.

    Comments

    Here in Tennessee, we’re just glad to have our thumbs. Don’t think for a second this will end up in the Southern Classrooms of the unprogressive. Christian ideology teaches us to deny, deny, deny as teachers are now allowed to bring Creationism into debate against hard facts like this new discovery. Read more about the pulpit in the classroom with some evolutionary artwork on my artist’s blog at http://dregstudiosart.blogspot.com/2012/04/pulpit-in-classroom-biblical-...

    KatSeiko
    These people would probably say that this is one of the fallen angels that the bible tells us about.. Fallen flat on their face.
    Sorry, could not resist the humor of that thought..
    Hank
    My gosh, crazy religious people must be stopped.  Good thing there were no religious people 20, 40, 60 or 80 or 100 years ago or America would not have gotten all those Nobel prizes!  I hadn't realized we were in some fundamentalist country.

    If you really want to stand up for science, tell progressives to stop risking millions of lives by campaigning against vaccines and genetically modified foods. Evolution education is minor compared to those two issues, it is just a few cranks in isolated areas - "unprogressive" people are a lot more accepting of science than progressives when lives are at stake. Compare the vaccine rate in any religious small town in Tennessee to Seattle.
    Chicken Vaccines Combine to Produce Deadly Virus by Kai Kupferschmidt on 12 July 2012
    At risk. Farmed chickens are dying from a recombined vaccine.

    Vaccines aren't supposed to cause disease. But that appears to be what's happening on Australian farms. Scientists have found that two virus strains used to vaccinate chickens there may have recombined to form a virus that is sickening and killing the animals. "This shows that recombination of such strains can happen and people need to think about it," says Glenn Browning, a veterinary microbiologist at the University of Melbourne, Parkville, in Australia and one of the co-authors on the paper.

    Chickens worldwide are susceptible to a group of herpesviruses called ILTV, which target their upper respiratory tract. The resulting disease, known as infectious laryngotracheitis (ILTV), reduces egg production and can kill up to one-fifth of those infected. "The birds effectively choke to death on blood and mucus," says Browning. The disease is not known to infect any other animals other than chicken and chicken-like birds.

    To combat ILTV, farmers vaccinate their chickens with attenuated herpesviruses that can still infect and replicate but do not lead to disease. Australia has used two vaccines, which are produced by Pfizer and called SA2 and A20. In 2006, however, the country purchased a new vaccine from European company Intervet called Serva. Two years later, new strains of ILTV, called class 8 and 9, appeared. They are just as deadly as other strains. "But they seem to be dominating over the strains that were reported prior to 2007," says Browning.

    Because the new strains appeared shortly after the European vaccine was introduced, scientists thought that the new vaccine strain might have reverted back to a disease-causing form. But when the researchers sequenced the genomes of the two new strains and the three vaccine strains, they found that the new viruses were actually stitched together from the European and Australian vaccines. Although it is not clear what mutations keep the vaccine strains from causing disease in the first place, they were probably lost when the viruses recombined, says Browning, whose team reports its findings online today in Science.

    Der, now who believes this the most, republicans or stupid democrats?

    HedgehogFive
    It seems that a lot of that sort of quarreling will be starting start in this column.

    For what it's worth, we Hedgehogs refer to your species as GGMMs -
    God's Genetically Modified Monkeys.

    rholley
    A Plasticine hominid:

    Robert H. Olley / Quondam Physics Department / University of Reading / England