John Endler studied color patterns in guppies that are found in streams in the tropical forests of Venezuela. He noticed that males and females were sexually dimorphic, with males displaying numerous bright spots and other colorations, while females were typically drab in color. However, in natural populations there is considerable variation in the brightness of male coloration, with males in some populations being very bright and males in other populations being less brightly colored. Endler did a series of experimental studies in natural and artificial environments, where he varied predation pressure by either introducing, or excluding guppy predators. He found that male guppies from high predation environments became less brightly colored over the course of several generations, while males in low predation environments became more brightly colored. Please explain these results.
John Endler studied color patterns in guppies that are found in streams in the tropical forests of Venezuela. He noticed that males and females were sexually dimorphic, with males displaying numerous bright spots and other colorations, while females were typically drab in color. However, in natural populations there is considerable variation in the brightness of male coloration, with males in some populations being very bright and males in other populations being less brightly colored. Endler did a series of experimental studies in natural and artificial environments, where he varied predation pressure by either introducing, or excluding guppy predators. He found that male guppies from high predation environments became less brightly colored over the course of several generations, while males in low predation environments became more brightly colored. Please explain these results.
