* Supersoldier Ants * Quasicrystals from Space * A Dog in Wolf's Clothing * Alarm follicles * The Sacred Headwaters *




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Supersoldier Ants

Thumbnail image for Thumbnail image for worker-supersoldier-raja2HR.jpgA worker ant with a supersoldier (Courtesy Alexander Wild)
McGill University biologist Dr. Ehab Abouheif had been studying the development of an ant species called Pheidole morrisi on Long Island in New York for 15 years -- enough time to get to know them really well. So you can imagine his surprise when he recently stumbled upon a colony that contained huge "monstrous" ants like none he had never seen before. These anomalies were similar to the "supersoldiers" that some ant species use to defend against army and fire ants in the southwestern U.S. Dr. Abouheif ran lab experiments to figure out where the anomalies came from. They showed the ability to develop into supersoldiers is a hidden genetic potential that can be activated by the right environment in a huge number of related ant species, even though most don't normally have supersoldiers. He believes similar mechanisms can play an important role in the evolution of many species -- not just ants. . 
     

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Quasicrystals from Space

Quasicrystal1.jpgAtomic model of a quasicrystal surface (J.W. Evans/Ames Laboratory/Wikimedia Commons)
The 2011 Nobel Prize in Chemistry was awarded to Israeli scientist Dr. Dan Schechtman for the discovery of quasicrystals, a completely new phase of matter. Schechtman initially faced scepticism from scientists who thought quasicrystals were impossible. After quasicrystals were confirmed to have been made in the lab, many scientists believed they were unstable and couldn't be created or persist in nature. But another quasicrystal pioneer, Dr. Paul Steinhardt, a professor of physics at Princeton University and Director of the Princeton Centre for Theoretical Science, thought otherwise. After a decade-long search, he came across a rock from a remote part of eastern Russia that contained perfect quasicrystals. Analysis showed that not only were the quasicrystals natural, but the rock was a meteorite that had formed in space 4.5 billion years ago.      
     

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A Dog in Wolf's Clothing

Thumbnail image for _54400219_dogcopy.jpgProfile of 33,000 year old canine skull from a cave in Siberia (Courtesy Susan Crockford)
A 33,000 year old skull found in a cave in Southern Siberia suggests we may want to reconsider what we thought we knew about the domestication of dogs.  Features of the skull, including its overall size and teeth indicate that it is an animal somewhere between a wolf and a dog -- a classic transitional fossil.  To Dr. Susan Crockford, a zoologist and evolutionary biologist at the University of Victoria in British Columbia, these features mean that wolf domestication was underway.  But the fact that this lineage did not survive the Ice Age 25,000 years ago, suggests that the domestication of dogs likely happened more than once and in many different places.  It also might suggest that we didn't tame wolves to create dogs, but instead some wolves occupied the ecological niche created by human settlements.  In effect dogs domesticated themselves by reaping the benefits of living near and within these human groups.
      

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Alarm follicles

800px-Adult_bed_bug,_Cimex_lectularius.jpgAdult bedbug feeding on a human host (Piotr Naskrecki/Wikimedia Commons)
Compared to other apes, many humans are relatively hairless.  But even those not blessed with copious visible hair do have a covering of fine body hair - the classic peach-fuzz.  In its thicker form, which is more common to men, it is called terminal hair.  The near invisible form, more common to women,  is called vellus hair.  Both types had been thought to be non-functional -- perhaps just an evolutionary left-over.  But new research by Dr. Michael Siva-Jothy, a Professor of Entomology in the Department of Animal and Plant Sciences at the University of Sheffield in England, suggests this fine hair may have at least one purpose.  It helps us detect the presence of ectoparasites such as bed bugs.  We feel them on the hair before they have a chance to bite and these fine hairs also create a physical barrier for the bed bugs, making it more difficult for them to reach the skin.. 


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The Sacred Headwaters

sacred_headwaters.jpgThe Iskut River flowing south into Kinaskan Lake (Greystone Books)
In a remote and rugged corner of north-western British Columbia, three of Canada's most important salmon rivers begin their long trek to the ocean. They are the Stikine, Skeena and Nass Rivers. And the area where they are born is a spectacular valley known to the local First Nations as The Sacred Headwaters.  Now this pristine and unique ecosystem is under threat from three separate mining proposals - and that's got a lot of people upset. One of those people is Canadian author, anthropologist, and explorer-in-residence at the National Geographic Society, Dr. Wade Davis. His new book, The Sacred Headwaters, chronicles the history of the region and the battle to save the area from industrial development.


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