Lessons from a 28 Year-Long Evolutionary Experiment - The Extremo Files : The Extremo Files
http://blogs.discovermagazine.com/the-extremo-files/2016/08/29/353/
Every morning, a scientist walks into a lab in East Lansing, Michigan, grabs a pipette, and mixes two liquids. One is a cloudy brew of E. coli cells,
billions of organisms thick; the other is a sterile solution with glucose and essential nutrients. One part A, 99 parts B, and back in the incubator
it goes; over the next 24 hours, the cells will double nearly seven times, adapting to the broth in the process.
And so it goes in the lab of Richard Lenski, a Professor of Microbial Ecology at Michigan State University, just as it has for the last 28 years.
That’s more than 65,000 generations of E. coli, the “lab rat” of microbiology; the associated experiments have generated freezers’ worth of samples
and burned through enough petri dishes to fill a warehouse.
It started with 12 replicate populations of the same E. coli strain, each allowed to propagate on its own as it adapted to the glucose- and citrate-
containing food source. “Is evolution this invariable slow and gradual process?” Lenski recalls wondering as he set up the first agar plates. “What
about the repeatability – do things solve problems in the same way every time? Do you arrive at an end point that is optimal?”