Final answer:
Natural selection favors leapfrogging behavior in guppies to reduce individual predation risk by distributing this risk among the group. Endler's research illustrates natural selection affecting guppy coloration based on predator presence, with camouflaged colors in high predation areas and brighter colors in predator-free zones.
Step-by-step explanation:
The student asked why natural selection has favored leapfrogging behavior in guppies when approaching a predator. This behavior is hypothesized to reduce the individual predation risk for the guppies by sharing the risk among them as they take turns being closer to the predator. This distributed risk allows each guppy in the leapfrogging sequence an opportunity to assess the predator while minimizing the time any individual is at the highest risk position.
John Endler's studies suggest that traits such as coloration, which affect visibility to predators, undergo natural selection based on the presence or absence of predators. Guppies develop less conspicuous colors in areas with high predation to better camouflage themselves and avoid detection, whereas guppies in predator-free environments develop brighter colors due to sexual selection.
Such predation avoidance behaviors are examples of the wider context of evolutionary adaptations in predator-prey dynamics, including mechanical, chemical, physical, or behavioral adaptations.