A. Learning enables animals to deal with the demands of a changing environment. The importance of learning for survival appears obvious. Animals can change their behavior to get food when sources of food change.
Animals can learn new strategies to avoid predators when faced with a novel form of predation.
B. Learning has costs, as well as advantages. Learning takes time, and animal at risk prior to learning. If parents must teach survival skills to offspring, then fewer offspring could be afforded. To be successful as a species, learning is not necessary. Most species do not learn.