Tag Archives: data analysis

Evolution picks up hitchhikers

In a twist on “survival of the fittest,” researchers have discovered that evolution is driven not by a single beneficial mutation but rather by a group of mutations, including ones called “genetic hitchhikers” that are simply along for the ride. These hitchhikers are mutations that do not appear to have a role in contributing to an organism’s fitness and therefore its evolution, yet may play an important role down the road.

Researchers from Princeton University found in a study of 1,000 generations of adaptation in 40 yeast populations that about five to seven specific mutations, rather than just a one, are needed for an organism to succeed. The knowledge of how mutations drive evolution can inform our understanding of how tumors resist chemotherapeutics and how bacteria evolve resistance to antibiotics. The study was published July 21 in the journal Nature. (more…)

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Deep Biosphere Harbors Active, Growing Communities of Microorganisms

The deep biosphere—the realm of sediments far below the seafloor—harbors a vast ecosystem of bacteria, archaea, and fungi that are actively metabolizing, proliferating, and moving, according a new study by scientists at Woods Hole Oceanographic Institution (WHOI) and the University of Delaware (UD).

“This is the first molecular evidence for active cell division in the deep biosphere,” says WHOI postdoctoral investigator Bill Orsi, who was the lead author on the study. Previous studies and models had suggested cells were alive, but whether the cells were actually dividing or not had remained elusive. (more…)

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