Saturday October 13, 2007
Nobel Prize in Medicine and Physiology, Saber-tooth Pussycat, Lucy Locomotion, Prehistoric Plant Procreation, Losing our Permafrost I - Melville Island, Losing our Permafrost II - Problems of Peat
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Nobel Prize in Medicine and Physiology
Sir Martin Evans, courtesy Cardiff University
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One of the co-winners of this year's Nobel Prize in Medicine and Physiology was Sir Martin Evans, a professor of Mammalian Genetics at the University of Cardiff in Wales. Sir Martin Evans was recognized for his pioneering work in culturing embryonic stem cells, those very early cells that develop into every other cell type in the body. Through his culturing techniques and work being done in genetic manipulation, researchers were able to create mice with specific genes turned off. These "knockout" mice have gone on to become one of the most widely used tools in modern molecular medicine, increasing our understanding of normal development and a number of diseases.
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Sir Martin Evans' Research PageThe Announcement from the Nobel FoundationMore on Sir Martin Evans from the Nobel FoundationCardiff University information on Sir Martin Evan's workSaber-tooth Pussycat
Smilodon Skull courtesy the University of California Museum of Palaeontology |
One only has to notice its giant fangs to realize the saber-tooth cat was probably a pretty fearsome killer. But just because these fearsome felines had giant weapons in their mouths doesn't necessarily mean they were the most powerful cats around. Colin McHenry, a paleontologist at the University of Newcastle, Australia, used computers models to crash test the saber-tooth cat's skull and he found that when you compare them to the modern lion, these ancient animals had the bite of a pussycat. However, its teeth made it a precision killing machine nonetheless.
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Newcastle University news releasePaper in the Proceedings of the National Academy of ScienceThe Computational Biomechanics Research Group, University of NewcastleNature News story about the researchLucy Locomotion
How Lucy might have walked. Image courtesy Bill Sellers |
There is little doubt that Lucy, the fossil of our human ancestor Australopithecus afarensis, could walk if she wanted. But what if Lucy had wanted to run? Using computer simulations, Dr. Bill Sellers, a lecturer at the University of Manchester, studied Lucy's locomotion and discovered that she seemed to be missing an important component that modern humans use to run efficiently: the Achilles heel.
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Dr. Sellers' HomepageAnimal Simulations LaboratoryWeb page where you can view video simulation of Lucy walkingNews story from the British Association Festival of Science where the research was presentedPrehistoric Plant Procreation
Male Cycad Cone, courtesy Irene Terry |
The Australian Cycad is a plant whose roots go back almost 300 million years to the beginning of the Permian Era. They've survived almost unchanged through the Age of the Dinosaurs, up to the modern day. But it's only in the last few years that we've begun to appreciate their strange biology. Take, for example, pollination in this plant. Researchers have known for 20 years that insects called thrips take the pollen from male cones to female cones. It was Dr. Irene Terry, from the University of Utah, who discovered how the plants persuade the insects to move. Male cones on cycads heat up during the day, using chemicals to make them warm to the touch. This sets off the release of a strong perfume, which drives the insects out of the cones. The insects then fly around, and once the perfume levels drop, return to the cones. However, the female cones also produce the perfume, which attracts some of the thrips, moving the pollen between plants. It's an ancient and complicated system that may help explain how insect-bourne pollination got its start in the first place.
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Losing our Permafrost I - Melville Island
Melville Island, courtesy Scott Lamoureux
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One of the coldest places in Canada is Melville Island in the High Arctic. Most years, the summer temperature is about five degrees Celsius. But this past summer, temperatures on the island were climbing into the teens and low twenties. When Dr. Scott Lamoureux, from Queen's University in Kingston, arrived at the island in July, he discovered a very different place. The high temperatures had melted the permafrost twice as much as usual, and that had led to massive mudslides. In some cases, rivers were blocked, and entire hillsides had been displaced. He's concerned the land is going to take a long time to recover from the damage, and with increasingly warm weather, this may be just the start of much larger changes.
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Losing our Permafrost II - Problems of Peat
Thawing Permafrost, courtesy Merritt Turetsky |
Further south, many of the areas of permafrost contain large amounts of peat. When peat melts, it starts to breakdown, and bacteria begin to cause decay of the plant material. This has led many scientists to believe there will be massive releases of carbon dioxide as this plant material is lost. However, Dr. Merritt Turetsky, from Michigan State University, has shown the problem to be more complex than was previously thought. Because plants begin to grow where the permafrost decays, that actual leads to an uptake of carbon dioxide. On the other hand, the same soils are giving off large amounts of methane gas, a very important contributor to greenhouse emissions. Dr. Turetsky points to this as proof of how little we know about the global impacts of warming, and how important it is to minimize our impact.
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Dr. Turetsky's Research PageMichigan State University Release on the ResearchAbstract of Dr. Turetsky's Research in Global Change BiologyTheme music copyright Raphaël Gluckstein. Creative Commons License by-nc-nd-2.0
Musical stings courtesy of Beatsuite.com Music Library.
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