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Past Shows
October 3, 2009
 Download an MP3 of the entire program (22MB).
Welcome to the Family, Ardi
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Ardi - Illustration copyright 2009, J.H. Matternes
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For fifteen years, rumours have circulated in the world of anthropology about a mysterious fossil found in Ethiopia by a group led by Dr. Tim White, a paleontologist and Professor of Integrative Biology at the University of California at Berkeley, and his Ethiopian colleagues. Finally, Dr. White has unveiled the discovery as a new species of hominid. It's the oldest complete skeleton of any member of the human family tree and dates back 4.4 milliion years. It's called Ardipithecus ramidus. In a series of new papers, Dr. White and more than 40 colleagues from around the world, including Dr. Owen Lovejoy, a professor of Biological Anthropology from Kent State University, describe the fossils that were painstakingly recovered from over a large area of remote Ethiopian countryside. They've dubbed the most complete skeleton, that of a mature female, "Ardi" - but they have the partial remains of thirty other individuals. As well, the group collected fossils of many other creatures, plant remains and soil samples, so that they were able not just to reconstruct Ardipithecus, but also the environment in which it lived. The picture that has emerged is of a creature much less like a chimpanzee or gorilla than many had thought such a primitive hominid to be. It's a creature adapted both for erect walking, but also very comfortable in trees. What this suggests is that the common ancestor we share with the other apes is much less like current apes than had been supposed.
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To the Moon, LCROSS
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Illustration of LCROSS trailing rocket-stage impactor, courtesy NASA
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As any six-year-old knows, if you want to know more about something, you hit it with a rock. The mission planners on NASA's LCROSS mission didn't have a rock, but they had a used-up rocket stage, and they wanted to understand more about the moon, so they're going to smash the rocket into the moon at three times the speed of a rifle bullet. According to Dr. Anthony Colaprete, principal investigator on the LCROSS mission, this will make a crater 20m wide, and create a plume of ejected material six kilometres high. The point of all this is to scan the ejected material for water and ice, to determine more accurately just how much water is hidden in the permanently dark craters on the South Pole of the Moon.
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There's no Pain in Team
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Oxford Crew
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Ever wonder why people exercise hard in aerobics classes or on group bicycling rides, but rarely by themselves? Part of the reason might be that the brain seems to reward us particularly for working hard in a coordinated way with others. That's the conclusion suggested by research by Dr. Emma Cohen, a post-doctoral fellow at the Institute of Cognitive and Evolutionary Anthropology at the University of Oxford. She and her colleagues tested rowers from the Oxford rowing team and had them row individually and in groups, exerting similar effort. She then did a simple test of their pain threshold. The rowers who had exercised in the company of others had significantly higher pain threshold, which she attributes to the production of pain-damping brain chemicals called endorphins.
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Killer Whales Go Hungry
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Photo credit Robert Pittman
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Killer whales feed on a variety of fish, invertebrates, mammals, turtles and birds. But some populations of killer whale have developed specialized foraging behaviour and are very picky when it comes to diet. One of these populations is the resident killer whales found in the northeastern Pacific Ocean, off B.C. and Washington state. A recent study by Dr. John Ford, at the Fisheries and Oceans Canada, Pacific Biological Station in Nanaimo, has determined that resident killer whales have a strong preference for chinook salmon, even though other varieties of salmon are in much greater supply. As the chinook population rises and falls, so too does the number of resident killer whales. The whales seem to lack the capability to change their diet, even in time of need.
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Coyote in Wolf's Clothing
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Coyote/wolf hybrid, courtesy R. Kays
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Over the past 90 years, coyotes have expanded their geographical range to include all of eastern North America. Coyotes were forced to move from their traditional domain, the Great Plains, to the eastern forests. According to Dr. Roland Kays, the Curator of Mammals at New York State Museum, coyotes were able to do this successfully for a couple of reasons. One was the depletion of the wolf in the eastern forests, which created a niche for the coyote to fill. The other reason was that the coyotes moving east through Ontario were able to breed with the remnant wolf population to create a hybrid. The hybrid coyotes have taken on some wolf characteristics, including size, colour and dietary needs. And they have become the top predator in the Northeast, killing deer instead of mice..
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Theme music bed copyright Raphaël Gluckstein.
Creative Commons License by-nc-nd-2.0
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