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Monday, August 10, 2009

Extinction: Is It in the Genes?


Written by Phil Berardelli
ScienceNOW Daily News 7 August 2009

"Sometimes it's just a case of being a member of the wrong family. Researchers analyzing evidence from 200 million years of fossil records have concluded that some lines of living organisms don't need a cataclysmic event to wipe them out. They just seem destined to go extinct."

The long and varied history of life on Earth is riddled with extinctions. They can signal the end of a species, a genera, or even a whole family of creatures. Sometimes they come suddenly and massively, as in the catastrophe that befell Earth at the end of the Cretaceous period, 65 million years ago. Or they can occur, as in the present day, when single species lose their habitats and quietly fade away. Evolutionary biologists have been studying these phenomena for more than a century, but they seem to have left a third extinction scenario largely unexplored: the possibility that certain types of creatures are simply more prone to dying out, irrespective of outside causes."

"That's what evolutionary biologists Kaustuv Roy of the University of California, San Diego, Gene Hunt of the Smithsonian Institution in Washington, D.C., and David Jablonski of the University of Chicago in Illinois decided to explore. The trio examined the extinction rates of marine bivalves--including clams, oysters, mussels, and scallops--whose tough, calcium-carbonate-based shells make them ideal for preservation. Using a global database that includes the evolutionary relationships and fossil record of 1678 types of bivalves spanning about 200 million years, the researchers found a close correlation between the disappearances of some genera and their closest genetic relatives, the researchers report today in Science. This correlation could not have happened at random, they conclude, so certain categories of creatures must contain genetic traits that make them more vulnerable to extinction."


To read the remainder of this article go to:http://sciencenow.sciencemag.org/cgi/content/full/2009/807/1


Source of image:http://upload.wikimedia.org/wikipedia/commons/9/98/Shell_Island_1985.jpg

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Thoughts worth thinking about

"Our subconscious minds have no sense of humor, play no jokes and cannot tell the difference between reality and an imagined thought or image. What we continually think about eventually will manifest in our lives."-Sidney Madwed



Laws alone can not secure freedom of expression; in order that every woman and man present their views without penalty, there must be spirit of tolerance in the entire population.- Albert Einstein Too often we underestimate the power of a touch, a smile, a kind word, a listening ear, an honest compliment, or the smallest act of caring, all of which have the potential to turn a life around. - Leo Buscaglia



A person's true wealth is the good he or she does in the world. - Mohammed



Our task must be to free ourselves... by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty. -Albert Einstein



The best way to find yourself, is to lose yourself in the service of others. - Ghandi



The unselfish effort to bring cheer to others will be the beginning of a happier life for ourselves. - Helen Keller



Aim for success, not perfection. Never give up your right to be wrong, because then you will lose the ability to learn new things and move forward with your life. Remember that fear always lurks behind perfectionism. Confronting your fears and allowing yourself the right to be human can, paradoxically, make yourself a happier and more productive person. - Dr. David M. Burns



Life is as dear to a mute creature as it is to man. Just as one wants happiness and fears pain, just as one wants to live and not die, so do other creatures. -His Holiness The Dalai Lama



Mankind's true moral test, its fundamental test (which lies deeply buried from view), consists of its attitude towards those who are at its mercy: animals. And in this respect mankind has suffered a fundamental debacle, a debacle so fundamental that all others stem from it. -



Milan Kundera, The Unbearable Lightness of Being



The worst sin towards our fellow creatures is not to hate them, but to be indifferent to them. That's the essence of inhumanity. -George Bernard Shaw

Ego's trick is to make us lose sight of our interdependence. That kind of ego-thought gives us a perfect justification to look out only for ourselves. But that is far from the truth. In reality we all depend on each other and we have to help each other. The husband has to help his wife, the wife has to help the husband, the mother has to help her children, and the children are supposed to help the parents too, whether they want to or not.-Gehlek Rinpoche Source: "The Best Buddhist Writing 2005 pg. 165

The hostile attitude of conquering nature ignores the basic interdependence of all things and events---that the world beyond the skin is actually an extension of our own bodies---and will end in destroying the very environment from which we emerge and upon which our whole life depends.