Many aspects of animal behavior increase the reproductive fitness of an organism. They may ensure an animal is able to reproduce. They may help an animal stay strong and healthy. They may also help an animal avoid unnecessary conflict. All these traits help ensure that an animal will be healthy enough to reproduce. Natural selection and animal biochemical behavior favors the organisms with the best adaptive traits for a given environment.
Evolution reflects the changes to the gene pool of a population over time in response to changes in the environment. Some changes can be directed by behavior. For example, wildlife in urban settings quickly adapts to the activity of humans, becoming active when there are less likely to be encounters. Encounters with humans waste precious energy. The same applies to nocturnal animals in response to predator behavior.
If being active at night is adaptive, natural selection may favor, those animals with coats which provide better camouflage or animals which develop adaptations to allow them to see better at night. Similar adaptations can be seen in biochemical behavior.
Examples of biochemical behavior include scent marking. These adaptations allow animals to conserve energy. Scent marking, for example, defines an animal’s border. Other animals intruding on another’s territory recognize that the area is claimed by another.
This action serves an important function. It allows the resident animal to mark its territory without having to constantly patrol it, thus saving energy. It also acts as a warning signal to intruders in that it may help prevent conflict and waste of energy. Conflict is not adaptive if it does not improve reproductive fitness.
Indirectly, there are benefits to the environment. It can help maintain the ecological balance between organisms, avoiding too many predators in a given area which may deplete prey populations.
Defensive spraying is another example of the relationship between natural selection and animal biochemical behavior. In the same way that scent marking helps prevent conflict, so too does spraying help an animal. A skunk may stamp its feet as a warning before finally turning to spray at a predator.
According to the national wildlife control firm, Critter Control, a skunk can accurately spray from 10 to 15 feet away. The spray effectively disarms a predator, allowing it to escape. Natural selection favored accurate spraying over time, allowing this behavior to serve its purpose.
Because of evolution, natural selection and animal biochemical behavior share a link which reflects how natural selection drives the development of certain adaptive behaviors and the physiology to support it. The result is an animal which is better equipped to reproduce.
Natural selection has favored the behavioral and genetic changes which enable animals to conserve energy and resources. Whether it is a biochemical behavior which prevents fighting or helps them find a mate, animals adapt to change in their environment so they can reproduce and pass their genes onto the next generation.
Mark Ridley. Animal Behavior: An Introduction to Behavioral Mechanisms, Development, and Ecology. 1995
Willmer, Pat, G. Stone, Ian A. Johnston. Environmental Physiology of Animals. 2000.