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Past Episodes: June 2010 Archives

Saturday June 26, 2010

Australopithecine "Big Man" Pigeons Make a Deal, Confused Parasitic Ducks, Bringing up Baby, Keeping the Bees. Web Extras: Fact or Fiction Mosquitos and Dark Clothes, Heat Tolerant Corals, Devonian Fish.

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Australopithecine "Big Man"
june26-2010-kadanuumuu.jpg Kadanuumuu, courtesy Y Haile-Selassie, L Russell, Cleveland Museum of Natural History, PNAS


One of the most famous fossils in anthropology is "Lucy", the Australopithecus afarensis discovered in Ethiopia in 1974. Lucy was 3.2 million years old and is seen as an important transitional fossil between our common ancestor with the chimpanzee and early humans. Lucy's skeleton, however, was incomplete and left important questions unanswered about her posture and whether she walked and ran like a human. Now a new, much larger and older skeleton of an Australopithecus has been found and analyzed by Dr. C. Owen Lovejoy, University Professor of Biological Anthropology at Kent State University, and his colleagues. This fossil, which they've called Kadanuumuu or "big man" in the Afar language, is also incomplete, but preserves bones that weren't found in Lucy. Dr. Lovejoy says that it confirms that Australopithecine were capable walkers and runners and also suggests that the common ancestor we had with chimpanzees was less like a chimp, and more like a human than we might have previously suspected.

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Pigeons Make a Deal

june26-2010-pigeon.jpg But they're terrible at Jeopardy

The Monty Hall Dilemma is a tricky problem in probability that is profoundly counter-intuitive for most people. Based on the problem posed in the game show, Lets Make a Deal, it basically asks if you should switch your pick after Monty Hall has shown you that one of the three doors hiding prizes doesn't have the prize. Most humans - including professional mathematicians - misjudge the probability, and choose wrong. However, Dr. Wally Herbranson, a professor of Psychology at Whitman College in Washington, tested his pigeons on a version of the game, and discovered once they'd played it enough to be familiar with it, they chose right every time.

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Related Links

external site - links will open in a new windowPaper in the Journal of Comparative Psychology
external site - links will open in a new windowLiveScience blog
external site - links will open in a new windowDr. Herbranson's profile

Confused Parasitic Ducks

june26-2010-redhead.jpg Redhead duck, copyright cc-by-3.0 Kevin Bercaw

Some birds, most famously the European Cuckoo, lay their eggs in other birds' nests. so that they can foist the labour-intensive and costly business of raising chicks - a phenomenon known as "brood parasitism." Dr. Mark Hauber, a professor of Psychology at Hunter College of the City University of New York, wondered if this introduced a problem for these chicks. It's well known that the chicks of some birds will "imprint" on whomever raises them - for example, goslings raised by humans behave as if the human is their parent, and think that they're humans as well. Dr. Hauber wondered if this imprinting happens in these parasitic bird chicks, and if it causes them to be confused about which species they are and who is a potential mate. In an experiment with Redhead ducks, which will lay their eggs in other ducks' nests, he found that the parasitic redhead chicks were confused about mates, and courted ducks of their foster-parents' species. This may explain why this kind of parasitism is not more common.

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Related Links
external site - links will open in a new windowPaper in Royal Society Proceedings Biology
external site - links will open in a new windowBlog by biologist R. Ford Dension
external site - links will open in a new windowDr. Hauber's Lab

Bringing Up Baby

june26-2010-baby_monkey.jpg Two male Barbary macaques interacting with an infant. Photo by Dr. Julia Fischer.

Barbary macaque monkeys live in Morocco and Algeria, and they are known for the extended care the males provide for infants. But the purpose of this behaviour has been unclear until it was studied recently. Dr. Julia Fischer, the Head of the Cognitive Ethology Laboratory at the Primate Centre in Gottingen, Germany, has found that male macaques like to take an infant around with them, as a way of bonding with other males, especially males higher in the social order. The infants, not necessarily their own, are used as a kind of passport for friendship. Together, males will hold the infant up, pass it around and make lip smacking noises in approval. Not only does having an infant in tow make a male more approachable, it makes him less likely to be attacked. Even though caring for an infant causes great stress for the male, the ability to bond and improve social status is deemed a worthy trade-off.

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Related Links
external site - links will open in a new windowPaper in Animal Behaviour
external site - links will open in a new windowDr. Fischer's web page
external site - links will open in a new windowDiscover Magazine Blog

Keeping the Bees

june26-2010-keeping_bees.jpg

There are over 19-thousand species of bees found all over the world, including two species that have been found near the edge of glaciers in the Arctic. It is estimated that bee pollination is key for about one-third of the world's food supply, either directly or indirectly. Bees play a vital role in the ecology of the planet, yet these unsung heroes of the natural world may be at risk. Pesticides, fragmentation of habitat and climate change all pose threats to bees. And according to Laurence Packer, if they are in trouble, then so are we. Dr. Packer is a melittologist and a Professor of Biology at York University in Toronto. In his new book, Keeping The Bees - Why All Bees Are At Risk and What We Can Do to Save Them, he writes about common misconceptions, some of the more exotic species he has encountered, and suggests simple ways ordinary people can help bees. 

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Related Links
external site - links will open in a new windowKeeping the Bees - Harper Collins
external site - links will open in a new windowYork University news release
external site - links will open in a new windowDr. Packer's web page

Web Extra - Science Fact or Science Fiction: Mosquitos and Clothing

From time to time, we present a commonly held idea or popular saying - and ask a Canadian scientist to set us straight on whether we should believe it or not. And today's popular belief is - mosquitoes are attracted to darker coloured clothing. To get to the truth, we contacted Dr. Rob Anderson, an entomologist and Biology Professor at the University of Winnipeg. He says it is science fact.

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Web Extra - Heat-tolerant Corals

Dr. Iliana Baums, a biologist from Penn State University, has been studying different populations of corals in the Caribbean to see if there are genetic variants that will allow some of them to survive the climate warming that has been implicated in coral bleaching and reef decline.

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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 Penn State


Web Extra - Devonian Fish

Lauren Sallan, a paleontologist and PhD candidate at the University of Chicago, has found that the major groups of fish that dominated the oceans in the Devonian period didn't fade away, but were wiped out in a geological eye blink, making room for the ancestors of modern fish and for the ancestors of all land animals. 

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Related Links
external site - links will open in a new windowPaper in PNAS
external site - links will open in a new windowNews release from the National Science Foundation

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Saturday June 19, 2010

Aquaculture: The Future of Farming the Water, Fish for Brains, Oldest Fig Wasp and more

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Aquaculture - The Future of Farming the Water

june19-2010-aquacage.jpg The feed barge and trout cages at Aqua-Cage Fisheries on Georgian Bay, courtesy Steve Naylor

Aquaculture is the world's fastest growing food production system, and now rivals wild capture fisheries as a source of the world's seafood. In many ways, you might see this as the logical progression of our shift from hunting and gathering food to domesticating it and growing it ourselves. We first did it on land with agriculture, and now we're doing it in the water. Despite our perception here in Canada, aquaculture is not just salmon, by any means. A huge proportion of the world's aquaculture is seaweed and shellfish. When it comes to fish, most are freshwater species, like carp, which are farmed using traditional methods in Asia that are thousands of years old. Aquaculture has enormous potential to provide even more food to the world's growing population. But it suffers from many of the pitfalls we faced with agriculture, especially when pursued as a large scale, capital-intensive, industrial system. The biggest concerns are environmental, as aquaculture can have impact on wild species and habitat. Fish-farming, in particular, shares many of the problems that land-based high-density animal farms have. Disease and parasites can be a significant problem, as they can spread in high-density fish farms, and there are worries that they might then create problems for wild fish. High-density fish farms also produce high-density fish waste. There are also conflicts over use, as the best sites for fish-farms can be near recreational areas, and fish farming can be perceived as the intrusion of a new industrial activity on natural ocean ecosystems. Researchers are looking for solutions to the technical problems associated with aquaculture, but society is ultimately going to have to decide just whether we're wise enough to domesticate the waters, the way we've domesticated the land.

Appearing in this program are:

  • Mr. Gord Cole, owner and operator of Aqua-Cage Fisheries, a rainbow-trout farm operation on the Wasauksing First Nation near Parry Sound, Ontario.
  • Dr. George Leonard, Aquaculture Program Manager for Ocean Conservancy, a US-based environmental group.
  • Dr. Thierry Chopin, professor of Marine Biology and aquaculture researcher at the University of New Brunswick, St. John.
  • Dr. Laura Halfyard, aquaculture researcher and Professor at the Marine Institute of Memorial Univerisity of Newfoundland.

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Related Links
external site - links will open in a new windowDr. George Leonard
external site - links will open in a new windowDr. Thierry Chopin's Lab
external site - links will open in a new windowDr. Laura Halfyard
external site - links will open in a new windowUN FAO (Food and Agriculture Organization) Aquaculture Department
external site - links will open in a new windowDepartment of Fisheries & Oceans Canada, Aquaculture site
external site - links will open in a new windowOcean Conservancy Aquaculture page
external site - links will open in a new windowWorld Wildlife Fund Aquaculture Program

Fish for Brains

june19-2010-braun.jpg Archaeologist Dr. David R. Braun at the fossil site in northern Kenya

Apes and humans are similar in many ways, in terms of biology and behaviour. But one of the key differences is the size of our brains. Although humans have bigger brains, it has been the subject of great debate as to why and how that came to be. But a new discovery by Dr. David Braun, an Archaeologist from the University of Cape Town, has shed new light on this discussion. Beneath a layer of volcanic ash on the shore of Lake Turkana in Northern Kenya, he excavated hundreds of bones, and several thousand stone tools, dating back 1.95 million years. The site included many catfish bones and at least 15 other fish, as well as turtle and crocodile, which show signs of having been cut with the stone tools. It provides the earliest definitive evidence of early humans butchering and eating aquatic animals. By expanding their diet to fish and seafood, early humans were adding the fatty acids essential for brain growth.

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Related Links

external site - links will open in a new windowPaper in PNAS
external site - links will open in a new windowNews release from George Washington University
external site - links will open in a new windowNews release from Johns Hopkins University
external site - links will open in a new windowDr. Braun's web page 

Oldest Fig Wasp

june19-2010-wasp.jpg 34-million-year-old fig wasp fossil. The arrow indicates the pocket where the pollen is stored. Courtesy Natural History Museum.
A fossil found on the Isle of Wight in England more than 100 years ago, and first identified as an ant, has now been correctly identified as a 34-million-year-old fig wasp. It is the oldest known fig wasp fossil. The wasp is almost identical to the modern species, which proves that this tiny but specialized insect has remained virtually unchanged for that many years. Dr. Stephen Compton, a Senior Lecturer from the Faculty of Biological Sciences at the University of Leeds, made the identification. He said the key was the pollen pocket on the underside of the wasp; it still contained pollen from a fig tree, albeit fossilized. The age of this fossil points to the fact that the complex relationship that exists today, between the fig wasp and its host trees, developed more than 34 million years ago, and has remained unchanged since then.

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Related Links
external site - links will open in a new windowPaper in Royal Society Biology Letters
external site - links will open in a new windowNews release from the University of Leeds
external site - links will open in a new windowNews release from the British Natural History Museum
external site - links will open in a new windowDr. Compton's web page

Theme music bed copyright Raphaël Gluckstein.
Creative Commons License by-nc-nd-2.0 
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Saturday June 12, 2010

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)

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

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