What defines a critical period in animal development?

A critical period in animal development is defined as a specific time frame during which an animal is particularly receptive to learning certain behaviors or skills. During this window, experiences or stimuli can have profound effects on the development of various traits and behaviors. For instance, certain socialization experiences in young animals, such as exposure to other species or environments, can significantly shape their future behavior and interactions. If these experiences do not occur during the critical period, the animal may develop certain deficiencies or socialization challenges later in life.

Other options, while they may describe aspects of animal behavior or development, do not capture the essence of a critical period. The times when animals are most active, the age of physical maturity, or periods of heightened stress relate to different aspects of animal behavior and development but do not specifically denote the critical window for learning specific behaviors.