What does the window exhort bacteria to do in "Molecular Evolution" by Tina Hesman Saey? An excerpt from "Molecular Evolution" by Tina Hesman Saey: > Inside the lab, a dozen glass flasks containing clear liquid swirl in a temperature-controlled incubator. Although the naked eye can't see them, millions of E. coli bacteria grow in the flasks, **doing what the window exhorts**. Lenski started the cultures in 1988, intending to follow the course of natural selection for several hundred generations. Now, two decades later, the cultures are still growing and have produced more than 45,000 generations of bacteria each. Though it doesn't look like a work of literature, the bold text does sounds figuratively. I understand every word, yet I still can't grasp what exactly bacteria do. What does the window exhort bacteria to do?

The paragraph immediately before the one you quote is:

> Richard Lenski, an evolutionary biologist at Michigan State University in East Lansing, is among the scientists hitting the rewind button on evolution. Meter-high letters taped to the windows of his lab spell out the lab's motto: EVOLVE. In the center of the "O," the face of Charles Darwin peers out toward the football stadium.

(From freelibrary)

Therefore the window exhorts them to Evolve.