Source: Evolution Web site
Mating in the wild can be dangerous business, especially when the bright colors, big tails, and flashy patterns some animals use to attract potential mates can also attract predators. In this Evolution feature, based on a famous experiment by John Endler, users create virtual streams and stock them with bright to drab male guppies and up to three different predators. With each simulation, the guppy population changes due to selection pressure from both predators and mates.
When evolutionary biologist John Endler began studying Trinidad's wild guppies in the 1970s, he was struck by the wide variation among guppies from different streams, even among guppies living in different parts of the same stream. Males from one pool sported vivid blue and orange splotches along their sides, while those farther downstream carried only modest dots of color near their tails. Endler also observed differences in the distribution of guppy predators, and in the color and size of the gravel in different stream locations.
Endler photographed hundreds of guppies and carefully recorded their size, color, and the size and placement of their spots. He began to see a strong correlation between where guppies lived in a particular stream and whether the fish were bright or drab. But what was responsible for these trends in coloration? And if bright colors made guppies more conspicuous to predators, why should males be colorful at all? Endler formed a hypothesis based on his observations, then set out to test it. His results would prove to be one of evolutionary biology's most important discoveries.
Academic standards correlations on Teachers' Domain use the Achievement Standards Network (ASN) database of state and national standards, provided to NSDL projects courtesy of JES & Co.
We assign reference terms to each statement within a standards document and to each media resource, and correlations are based upon matches of these terms for a given grade band. If a particular standards document of interest to you is not displayed yet, it most likely has not yet been processed by ASN or by Teachers' Domain. We will be adding social studies and arts correlations over the coming year, and also will be increasing the specificity of alignment.