* Making Life Multicellular * The Cambrian Tulip Patch * Telltale Telomeres * When Savvy Snakes Squeeze * A Universe from Nothing *


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Making Life Multicellular


Single celled organisms dominate life on our planet.  They rule in diversity and in numbers.  But at some point back in deep time, a group of unicellular organisms decided to team up -- to put the group ahead of the individual.  Simple multicellular creatures began to appear, and their descendants are today's plants and animals.  Since staying single-celled is clearly still such a popular option, evolutionary biologists are still puzzled by the question of how and why multicellularity appeared.  New research by Dr. Michael Travisano, from the Department of Ecology, Evolution and Behaviour, and the  Biotechnology Institute at the University of Minnesota in Saint Paul, and his colleagues may have hinted at an answer.  The evolution of multicelluar organisms might  have taken billions of years of evolution in Nature, but it took only weeks in his lab.   

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A Cambrian Tulip Patch

in-300-sea-creature-fig-2-r.jpg Reconstruction of Siphusauctum gregarium.(Marianne Collins/ROM/U of T/PLoS One)
The last thing you expect to find in a 500-million-year-old fossil deposit like the Burgess Shale is a patch of tulips.  After all, flowering plants didn't evolve until hundreds of millions of years later, and besides, the Burgess Shale preserves a marine ecosystem.  So it wasn't that surprising when Lorna O'Brien, a PhD candidate at the Department of Ecology and Evolutionary Biology at the University of Toronto, got a closer look at these fossils and confirmed that they weren't in fact tulips.  What they were, however, was surprising.  They were filter feeding animals with a unique feeding apparatus that seems to be like nothing on Earth today.
      

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Telltale Telomeres

young-middle-aged-old-zebra-finches-courtesy-paul-jerem-Telemeresmall.jpg Young, middle aged and old zebra finches.(Courtesy of Paul Jerem)
What's your probability of dying young or living to a ripe old age? That's something a peek at your DNA may be able to reveal. Dr. Britt Heidinger of the University of Glasgow and her colleagues found that the future lifespan of zebra finches was related to how long critical segments of their DNA, called telomeres, were when they were young. Long teleomeres predicted long life, and short ones? Well, don't bother with that avian pension fund. Dr. Heidinger suggests that it's possible that similar correlations might be expected in humans.


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When Savvy Snakes Squeeze

Boa-squeezing-rat-sboback.jpg (Courtesy of Scott Boback)
Boa constrictors are predators feared for their ability to squeeze the life out of their prey. However, knowing when to stop squeezing is very important - if they let go too soon, their prey may fight back or escape, and if they squeeze too long, they waste precious energy. Dr. Scott Boback, a biologist at Dickinson College in Carlisle, Pennsylvania, wanted to find out how snakes know when to stop squeezing. So in an experiment using dead rats and a mechanical heart, he discovered that they keep close tabs on the beating of their victims' heart.
     

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A Universe from Nothing

Universe-from-Nothing-cover.jpg

A little over 13 billion years ago, our universe sprang into existence.  And physicists now have a pretty good picture of what happened from the first fractions of a second after that moment to the present day.  But why do we have a universe at all?  Why is there something rather than nothing?  That's the question renowned physicist Lawrence Krauss attempts to answer in his new book - A Universe from Nothing:  Why there is Something Rather than Nothing.   You'll be surprised just how interesting nothing actually can be.   Dr. Krauss is the Foundation professor and director of the Origins Project at Arizona State University.

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