The ethological concept of species-typical behavior is based on the premise that certain behavioral similarities are shared by almost all members of a species. Some of these behaviors are unique to certain species, but to be 'species-typical' they do not have to be unique, they simply have to be characteristic of that species.

Species-typical behaviors are almost always a result of similar nervous systems and adaptations to the environment in organisms of the same species. They are created and influenced by a species' genetic code and social and natural environment. Hence, they are strongly influenced by evolution.

A classic example of species-typical behavior is breast crawl: the vast majority of human newborns, when placed on a reclined mother's abdomen, will find and begin to suckle on one of the mother's breasts without any assistance.

Species-typical behaviors are occasionally tied to certain structures of the brain. Murphy, MacLean, and Hamilton (1981) gave hamsters brain lesions at birth, which destroy certain brain structures. They discovered that while hamsters still expressed species-typical behavior without a neocortex, they lost much of their species-typical play and maternal behaviors when deprived of midline limbic convolutions. Likewise, if squirrel monkeys lose their globus pallidus, their ability to engage in certain sexual behavior (e.g. thigh-spreading, groin-thrusting) is either eliminated or impaired.

Scientists may also use stimulation to discover the role of a structure in species-typical behavior. In a 1957 experiment, physiologist Walter Hess used an electrode to stimulate a certain part of a resting cat's brainstem; immediately after the stimulation, the cat stood up and arched its back with erect hair—a species-typical behavior in which cats engage when frightened. The behavior lasted as long as the stimulation lasted and ended as soon as the stimulation ended. Later experiments revealed that even if the same part of the brain is stimulated with the same amount of energy for the same period, the intensity of the elicited behavior changes depending on the context. In 1973, behavioral physiologist Erich von Holst attached an electrode to one part of a chicken's brainstem. When briefly stimulated without any unusual environmental factors, the chicken was restless. When briefly stimulated in the presence of a human fist, the chicken reacted with a slightly threatening posture, and in the presence of a weasel, the chicken took a very threatening pose, with feathers bristling. The brainstem, in this case, elicits species-typical behavior that is appropriate to the surrounding environment.

The presence or density of certain chemical receptors on cranial structures such as the brainstem often determines their importance in one species-typical behavior or in other species. For example, monogamous prairie voles have a high density of oxytocin receptors (OTRs) in the nucleus accumbens, while non-monogamous meadow voles do not.

The manner in which hormones alter these receptors is an important behavioral regulator. For example, gonads affect OTRs in different rodents. In female rats, gonadal estrogen increases the level of OTR binding and, when the ovarian cycle maximizes the amount of estrogen in the bloodstream, causes OTRs to appear in ventrolateral regions of the structure called the ventromedial nucleus. This, in turn, increases the likelihood that a female rat will engage in certain species-typical sexual activity by increasing her sexual receptivity. But the effect of this regulatory mechanism differs between species; though a gonadectomy would decrease (and gonadal steroids would increase) sexual receptivity in the female rat, these things would have opposite impacts on female mice.

While some species-typical behavior is learned from the parents, it is also sometimes the product of a fixed action pattern, also known as an innate releasing mechanism (IRM). In these instances, a neural network is 'programmed' to create a hard-wired, instinctive behavior in response to an external stimulus. When a blind child hears news that makes her happy, she's likely to smile in response; she never had to be taught to smile, and she never learned this behavior by seeing others do it. Similarly, when kittens are shown a picture of a cat in a threatening posture, most of them arch their backs, bare their teeth, and sometimes even hiss, even though they've never seen another cat do this. Many IRMS can be explained by the theory of evolution—if an adaptive behavior helps a species survive long enough to reproduce, such as a cat hissing to discourage an attack from another creature, then the genes that coded for those brain circuits are more likely to be passed on. A heavily studied example of a fixed action pattern is the feeding behavior of the Helisoma trivolvis (pulmonata), a type of snail. A study has shown that the intricate connections within the buccal ganglia (see nervous system of gastropods) form a central system whereby sensory information stimulates feeding in the Helisoma. More specifically, a unique system of communication between three classes of neurons in the buccal ganglia are responsible for forming the neural network that influences feeding.