Tag Archives: richard lenski

Bacteria Show Capacity for Rapid, Beneficial Mutations

AUSTIN, Texas — Scientists studying how microbes evolve have long assumed that nearly all new genetic mutations get passed down at a predictable pace and usually without either helping or hurting the microbe in adapting to its environment. In a new study published in the journal Nature, an international team of researchers studying tens of thousands of generations of E. coli bacteria report that most new genetic mutations that were passed down were actually beneficial and occurred at much more variable rates than previously thought. The finding could have implications for treating bacterial infections. (more…)

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No peak in sight for evolving bacteria

There’s no peak in sight ­– fitness peak, that is – for the bacteria in Richard Lenski’s Michigan State University lab.

Lenski, MSU Hannah Distinguished Professor of Microbiology and Molecular Genetics, has been running his evolutionary bacteria experiment for 25 years, generating more than 58,000 generations. In a paper published in the current issue of Science, Michael Wiser, lead author and MSU zoology graduate student in Lenski’s lab, compares it to hiking. (more…)

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Why Do Organisms Build Tissues They Seemingly Never Use?

EAST LANSING, Mich. — Why, after millions of years of evolution, do organisms build structures that seemingly serve no purpose?

A study conducted at Michigan State University and published in the current issue of The American Naturalist investigates the evolutionary reasons why organisms go through developmental stages that appear unnecessary.

“Many animals build tissues and structures they don’t appear to use, and then they disappear,” said Jeff Clune, lead author and former doctoral student at MSU’s BEACON Center of Evolution in Action. “It’s comparable to building a roller coaster, razing it and building a skyscraper on the same ground. Why not just skip ahead to building the skyscraper?” (more…)

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