Genetics

3-billion-year-old genetic fossil traced

Publication: msnbc.com   Date: December 20, 2010   View Article

The collective genome of all life on Earth today went through a rapid growth spurt between 3.3 billion and 2.8 billion years ago, according to scientists who used computer algorithms to reconstruct the evolutionary history of thousands of genes.

The growth spurt coincides with the advent of a biochemical pathway known as electron transport that is “integral for photosynthesis as well as for respiration,” Lawrence David, a computational biologist at the Massachusetts Institute of Technology, told me.

Tibetans Evolved to Survive Highlife, Study Says

Publication: National Geographic News   Date: May 13, 2010   View Article

Most Tibetans are genetically adapted to life on the “roof of the world,” according to a new study.

The Tibetan Plateau rises more than 13,000 feet (4,000 meters) above sea level. At such heights, most people are susceptible to hypoxia, in which too little oxygen reaches body tissues, potentially leading to fatal lung or brain inflammation.

To survive the high life, many Tibetans carry unique versions of two genes associated with low blood hemoglobin levels, the researchers found.

Dogs First Tamed in China – To Be Food?

Publication: National Geographic News   Date: September 4, 2009   View Article

Wolves were domesticated no more than 16,300 years ago in southern China, a new genetic analysis suggests—and it’s possible the canines were tamed to be livestock, not pets, the study author speculates.

“In this region, even today, eating dog is a big cultural thing,” noted study co-author Peter Savolainen, a biologist at the Royal Institute of Technology in Stockholm, Sweden.

Europe’s First Farmers Were Segregated, Expert Immigrants

Publication: National Geographic News   Date: September 3, 2009   View Article

Central and western Europe’s first farmers weren’t crafty, native hunter-gatherers who gradually gave up their spears for seeds, a new study says.

Instead, they were experienced outsiders who arrived on the scene around 5500 B.C. with animals in tow—and the locals apparently didn’t roll out the welcome wagon.

Biodiversity’s winners and losers

Publication: MSNBC.com   Date: August 17, 2009   View Article

There are winners and losers on the racetrack of speciation – the process of species splitting into new species, according to Michael Alfaro, an evolutionary biologist at the University of California Los Angeles. He and his colleagues analyzed DNA and fossils from 44 major lineages of jawed vertebrates to calculate which ones have exceptionally fast and slow rates of speciation.

Where Did Dogs Become Our “Best Friends”?

Publication: National Geographic News   Date: August 3, 2009   View Article

DNA from scrappy dogs in African villages is raising doubts about a theory that dogs first became “man’s best friend” in East Asia.

Based on DNA evidence, scientists believe that domestic dogs originated from Eurasian gray wolves sometime between 15,000 and 40,000 years ago.

Ancient Barley Could Help Farmers Adapt to Changing Climate

Publication: By John Roach   Date: July 27, 2009   View Article

DNA has been recovered from an ancient form of barley that persisted for more than 3,000 years and the tastes of five civilizations in Egypt’s upper Nile, according to a new study.

The barely was particularly well-adapted to the region’s parched climate, allowing it to trump more bountiful but less hardy varieties, according to genetic analyses of the preserved grains.

The finding could assist efforts to breed modern crops that are able to survive a drying climate, noted plant researcher Robin Allaby, an associate professor at the University of Warwick in the UK.

“If we find genes that have evolved to cope with arid conditions, we can then look to transferring those genes, or replicating those genes in modern varieties,” he explained to me in an e-mail exchange.

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© 2008-2010 Collected Writings By John Roach