Adapting to adversity to thrive

In 1978 a young graduate student from the University of Pennsylvania named David Reznick, packed his bags and set off to the Caribbean Island of Trinidad. His mission? To examine Charles Darwin’s concept of the struggle for existence – specifically, how predator-prey interactions impact the evolution of new species.

Armed with a topographical map traced onto a sheet of notepaper, Reznick collected 1 600 guppies, the prolific fish species whose