In the second simulation, you've again stocked your pool with about one hundred guppies, but this time you start the test with an even mix of all four guppy types (brightest, bright, drab ...

Sparked by the effectiveness of German U-boats, GUPPY aimed to modernize American submarines, starting with reverse engineering German Type XXI U-boats. -The program, which ran from 1947 to 1963 ...

Not only have guppy numbers more than doubled under the relatively low level of predation, but also, after only four guppy generations, the percentages of drab males to bright males have evened ...