The behavior of an animal is crucial in determining the success of that animal. Proper and efficient behavior is necessary if the animal is to obtain food, a nesting site, and mate or to successfully raise its young or deal with other ecological problems it faces. Behavior is as much of an evolutionary adaptation as are the morphology and physiology of the individual. Behavior can be selected for or against and behavior can evolve. Selection favors those behaviors that increase the individual's fitness, those behaviors that have the greatest benefits and least costs. Individuals with such adaptive behavior will be selected for and will pass on the genetic basis for such behavior to future generations. Different environmental or ecological conditions select for different types of behavior. For example, vertebrates exhibit a vast array and varying degrees of social behavior in dealing with offspring, potential mates, competitors, predators, and prey. The type of behavior exhibited is directly related to the ecological conditions under which the animals live. It seems fitting to end our examination of vertebrate biology with behavior, since behavior cuts across all other aspects of the animal's biology. Behavior is influenced by genetics, development, motivational states determined by hormones and other physiological conditions, the functioning of the nervous system, the anatomical structuring of the body, and, as you will see, the ecology of the animal.