Final answer:
Guttman and Kalish's study found that pigeons pecked the most at the reinforced color. This learned behavior can impact natural selection, as demonstrated in studies with yellow buntings' response to butterfly eyespots and John Endler's research on Trinidad guppies, which showed that predation impacts guppy coloration.
Step-by-step explanation:
The study by Guttman and Kalish in 1956 involving pigeons and the rate of pecking across different colors found that pecking rates were highest for the reinforced color. This behavior is an example of how organisms can demonstrate learned responses to specific stimuli, which can influence their survival and reproductive success. Such behaviors can impact the process of natural selection as seen in different species, including predators and prey.
In the case of the yellow buntings and butterflies, the buntings' responses to butterflies with eyespots (fleeing behavior) compared to those without can lead to selection pressures on the butterfly population. The butterflies with a feature that elicits a strong response, such as eyespots, may be selected against because they increase the likelihood of the predator fleeing rather than engaging, ultimately affecting their chances of survival and reproduction.
John Endler's work with Trinidad guppies (Poecilia reticulata) demonstrated a clear relationship between predation levels and coloration in guppies, with less predation leading to more conspicuous colors due to sexual selection, while higher predation resulted in less conspicuous colors for better camouflage.