The concepts of innate releasing mechanisms, fixed action patterns, and sign stimuli are described as are other major areas of early ethological study such as imprinting and drive. I end with a critique of the evolutionary approach taken by the early ethologists, focusing on their fondness for group selectionist arguments. Modern ethology maintains an interest in the natural behavior of animals. Many of the conceptual tools that appeared so nebulous in their original forms, e.g., innate releasing mechanisms, are now better understood in physiological terms. The example is the co-evolution of the auditory systems of bats and moths and I show how that sensory world in each species is tailored to meet demands imposed by the other species.
Animals are sensitive to relevant stimuli in their environments.
Orientation, Navigation and Rhythms . How animals orient themselves in their environments and find specific locations and destinations, sometimes over great distances, as in migration, is next discussed. While we have unraveled some of the mysteries of how animals get about, this topic is one where many questions remain unanswered. Behavioral Genetics . A critical issue in any discussion of the evolution of behavior is whether or not behavior has a genetic basis.