Snails on Meth, Oldest Shoe, Sharks Smell in Stereo, Foster Comets, Manufacturing Depression

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GUEST HOST: ALISON MOTLUK

Snails on Meth

june12-2010-snail_memory.jpg
Humans may drink to forget, but Dr. Ken Lukowiak has found that snails take methamphetamine to remember. Amphetamines are thought to have an impact on memory, and this may have importance in understanding their addictive properties. Dr Lukowiak, a professor of Physiology and Pharmacology at the University of Calgary, has been studying the fundamental properties of memory in snails for many years. In recent experiments, he and his colleagues tested the effects of methamphetamine on a simple memory task in molluscs, and found that the drug worked powerfully to help inscribe memories that were significantly stronger and more durable than normal. Dr. Lukowiak suspects that the drug works on a very basic level, changing gene expression in the neurons that form and hold memory.

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Related Links
external site - links will open in a new windowPaper in The Journal of Experimental Biology
external site - links will open in a new windowNews article in JEB
external site - links will open in a new windowNPR Blog
external site - links will open in a new windowDiscover 80beats blog

Oldest Shoe

june12-2010-old_shoe.jpg courtesy Department of Archeology, University College, Cork

A perfectly preserved, 5,500-year-old shoe has been unearthed in a cave in southern Armenia. It is from the Chalcolithic period, also known as the Copper Age. Dr. Ron Pinhasi, from the Archaeology Department at University College Cork, in Ireland, says it is the oldest leather shoe ever found. The one-piece cow-hide shoe, about a women's size 7, had been cut to shape and tanned with some form of plant oil. It was found laced up and stuffed with straw in a hand-dug pit inside the cave. It is believed the straw was intended to maintain the shape of the shoe, which supports the theory that it and other items found in the pit were intentionally placed there, rather than simply discarded. The cool, dry conditions in the cave, as well as the thick layer of sheep dung on the floor, resulted in exceptional preservation of the shoe and other artifacts.


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Related Links

external site - links will open in a new windowPaper in PLoS ONE
external site - links will open in a new windowNews release from University College Cork
external site - links will open in a new windowDr. Pinhasi's web page
external site - links will open in a new windowCBC News story

Sharks Smell in Stereo

june12-2010-smooth_dogfish.jpg Shark wearing smelling apparatus - courtesy Kalman Zabarsky, Boston University
Scientists tell us that sharks are misunderstood creatures. So, the fact that the scientists have misunderstood an important way in which sharks find prey is a little ironic. It used to be thought that sharks used their acute sense of smell to follow the increasing strength of the odor to their meal. However, Jayne Gardiner, a Canadian marine biologist and Ph.D. candidate at the University of South Florida in Tampa, and her colleagues, have demonstrated something different is going on. They realized water is often too turbulent for concentration to be a useful cue for tracking. They've found that, instead, the sharks use the different timing at which odors reach their nostrils, to determine direction - much the way we determine the direction of a sound by the timing difference at which it reaches our ears.

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Related Links
external site - links will open in a new windowPaper in Current Biology
external site - links will open in a new windowNews release from Cell Press
external site - links will open in a new windowNature News
external site - links will open in a new windowJayne Gardiner's web page

Foster Comets

june12-2010-halley_comet.jpg Halley's comet
Astronomers have been puzzled by the huge population of comets orbiting at a vast distance from our Sun - what's known as the Oort cloud. While there would have been lots of comets formed in the early solar system, most of them should have been thrown right out of the system into interstellar space by the gravitational disruption of the great planets, rather than captured in the distant reaches of the solar system. Dr. Martin Duncan, an astronomer at Queen's University in Kingston, and colleagues, have solved the problem of our plethora of comets. They suspect the solar system formed in a cluster with other newly forming stars. Our solar system would have thrown out most of its comets, but so would all the other systems. They caught some of our comets, and we caught some of theirs. Thus, many of the comets in the Oort cloud may be fosterlings from other systems.

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Manufacturing Depression

june12-2010-manufacturingdepression.jpgSome 30 million North Americans spend more than 10 billion dollars a year on anti-depressants. But is there really an epidemic of depression in North America? Or does it have more to do with drug marketing than medical science? Dr. Gary Greenberg is a psychotherapist in Connecticut, and the author of a provocative new book called Manufacturing Depression: The Secret History of a Modern Disease. In it, he asks whether our prevailing sadness is really a disease that needs to be cured - or just the human condition.

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Related Links
external site - links will open in a new windowManufacturing Depression - Publisher's web page
external site - links will open in a new windowDr. Greenberg's web page (with links to his articles)

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