A case of fun and games in a flask with a bacteriophage which developed virus progeny that lost ability to attack:

http://phys.org/news/2016-11-biologists-speciation-laboratory-flask.html

"In a month-long experiment using a virus harmless to humans, biologists working at the University of California San Diego and at Michigan State University documented the evolution of a virus into two incipient species—a process known as speciation that Charles Darwin proposed to explain the branching in the tree of life, where one species splits into two distinct species during evolution.

***

"To conduct their experiment, Meyer, Lenski and their colleagues cultured a virus—known as "bacteriophage lambda"—capable of infecting E. coli bacteria using two receptors, molecules on the outside of the cell wall that viruses use to attach themselves and then infect cells.

"When the biologists supplied the virus with two types of cells that varied in their receptors, the virus evolved into two new species, one specialized on each receptor type.

"The virus we started the experiment with, the one with the nondiscriminatory appetite, went extinct. During the process of speciation, it was replaced by its more evolved descendants with a more refined palette," explained Meyer.

"Why did the new viruses take over?

"'The answer is as simple as the old expression, 'a jack of all trades is a master of none'," explained Meyer. "The specialized viruses were much better at infecting through their preferred receptor and blocked their 'jack of all trades' ancestor from infecting cells and reproducing. The survival of the fittest led to the emergence of two new specialized viruses.'"

Comment: Their explanation of a new species is a real stretch. The old virus adapted to a new food supply and lost the ability to attack two different receptors, now concentrating on only one, which is less of an advantage than having two weapons at its command. Twisted thinking to support Darwin. All they proved is viruses can adapt to a new food supply a la' Shapiro.