* Playing Footsie with Lucy * Give a Fox a Bone * A Killer Diet * Kissing a Comet * Explaining the Seahorse * Dark Matter Detection? *

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Playing Footsie with Lucy


aa_foot.jpgA. afarensis foot bone and human foot. Courtesy K Cogndon, C WArd and E Harman
Australopithecus afarensis, the 3.2 million-year-old fossil, is best known from the fossil skeleton called Lucy, and represents an important transitional form between our ape-like ancestors and modern humans.  But Lucy, and other A. afarensis fossils, were missing critical bones in their feet that would tell scientists whether this creature had an ape-like or human-like foot.  Now Dr. Carol Ward, a professor of anatomy at the University of Missouri College of Medicine, and her colleagues, have found a critical foot bone that tells the story.  It confirms that Lucy and her species had a modern human-like arched foot, well suited to walking and running, but not so useful for grasping and climbing trees.

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Give a Fox a Bone

fox_skull.jpg The red fox skull from cemetery in Jordan, courtesy Lisa Maher
The earliest cemeteries in the Middle East were thought to have existed in the Natufian period, 15 thousand to 12 thousand years ago.  But Dr. Ted Banning, an anthropologist at the University of Toronto, and his colleague Dr. Lisa Maher, (also from U of Toronto, and the lead author and director of the excavations), have found an older one - the earliest cemetery in the region.  It is located in northern Jordan and dates back over 16 thousand years to a period called the Geometric Kebaran; a period not previously known for the use of cemeteries.  But of eleven human remains found at this site, two were buried along with red fox remains in a ritualistic manner.  A single fox skeleton was distributed between the two human graves.  This discovery suggests foxes may have been regarded in a similar way to that of dogs in later time periods; either as pets or hunting companions. 

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A Killer Diet

killer_attack.jpg
 Killer whale attacking a gray whale calf, Photo: John Durban
Every Spring, gray whales migrate north from the Pacific Ocean, off the coast of southern California, to the Bering Sea.  But their journey is slowed by the awkward trip around Unimak Island, in Alaska.  Dr. Lance Barrett-Lennard, a research scientist at the Vancouver Aquarium, has found that, at this point in the gray whale journey, a population of about 150 transient killer whales lays in wait for them.  For about one month, these killer whales feed exclusively on gray whale calves by, first, separating them from their mothers, then driving them into water at a desirable depth of 20 to 40 metres, where the calves are then attacked, drowned and eaten.  But surprisingly, the killer whales return a day later to continue feeding on the gray whale carcass.  This marks the first time such food storage behavior has been reported in whales. 

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Kissing a Comet


tempel 1.jpg Comet Tempel 1 after Deep Impact, courtesy NASA/JPL-Caltech/UMD


In 2005, NASA's Deep Impact Spacecraft delivered an impactor to the surface of the comet Tempel 1.  The idea was to study the 6-kilometre-wide comet's composition and photograph the crater resulting from the impact.  But dust particles raised by the impact prevented the spacecraft from capturing a clear image of the crater.  That is why the Stardust-Next spacecraft will take another look at Tempel 1 as they come within 200 kilometres of each other next week; the rendezvous will take place appropriately on Valentine's Day.  Dr. Joe Veverka, a Professor of Astronomy at Cornell University and the Principal Investigator on NASA's Stardust-Next Mission, is especially excited by the prospect of - for the very first time - having a second look at a comet, and in particular, the 'fresh' five-year-old crater on Tempel 1.  New images and analysis of dust particles will provide valuable information about the composition of Tempel 1 and comets in general.   

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Explaining the Seahorse

The seahorse seems like a creature more suited to fantasy than reality.  It's an attractive fish, but seems to have made many sacrifices for beauty.  Its belly-first posture makes it a terrible swimmer, and not well suited for pursuing prey or avoiding predators.  Dr. Lara Ferry, a biologist at Arizona State University, and her colleagues, have found one explanation for the seahorse's shape.  Its tilted head gives it a real advantage in closing the distance on the tiny crustaceans it eats.  When its prey are close, the seahorse can snap its head up remarkably quickly, and suck them in through its tube-like mouth..
   

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Dark Matter Detection?

dark matter.pngDark Matter - artist's impression
Dark Matter, thought to represent more than 3/4 of the matter in the universe, has never been seen or felt, since it is invisible and doesn't interact with normal matter.  Its presence has only been inferred from the gravitation pull it seems to exert.  But Dr. Dan Hooper, Associate Scientist at the Fermi Laboratory in Chicago, and an assistant professor of Astronomy and Astrophysics at the University of Chicago, thinks he's now seen another, more direct trace of dark matter: a glow of radiation from the centre of our galaxy that he thinks is the radiation from dark matter particles colliding and annihilating each other.
   

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Theme music bed copyright Raphaël Gluckstein, Creative Commons License by-nc-nd-2.0