Test tube evolution catches time in a bottle.
نویسنده
چکیده
For most living things, 24,000 generations is a daunting span of time. Go back that many human generations, or about 500,000 years, and Homo sapiens had not yet evolved. Even for the fruit flies beloved of geneticists, 24,000 generations equals about 1500 years. But in Richard Lenski's laboratory at Michigan State University in East Lansing, 24,000 generations ago is a recent memory. The year was 1988, when he and his students first introduced 12 genetically identical populations of the bacterium Escherichia colito their new homes: 50-milliliter flasks filled with sugary broth.
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عنوان ژورنال:
- Science
دوره 284 5423 شماره
صفحات -
تاریخ انتشار 1999