The dimensional concepts of evolution include ultimate and proximate distinction of behavior, the evolution pace, modern concepts of natural selection, and cultural evolution. Understanding of the behavior requires obtaining the ultimate and proximate explanations. The distinction is critical in explaining the evolution. The ultimate explanation concerns the behavior and its reasons. On the other hand, proximate explanation concerns the functioning of the behavior.
The explanatory perspectives of evolution are derived from an ethological tradition. The first explanation is the adaptive value involving competition for resources and self-protection. The second explanation is the origin of the behavior. The third explanation involves the development and subsequent modification of the behavior through experience. The fourth explanation involves the mechanisms of controlling the behavior.
Evolution is the gradual change of characteristics of an organism over the generations. Darwin founded the theory of evolution and proposed that organisms evolve with time. According to Darwin, the organism’s designed features leading to successful reproduction increase generation after generation. These organisms constitute a huge percentage of the population. In addition, with time the process of evolution requires the modification of the population. Change in the environmental conditions resulted into certain characteristics favored by the natural selection, which directed the process to a different way (Johnson, 2000).
Natural selection as the evolutionary process makes organisms to develop and adopt changes needed in struggle for reproduction and survival. The natural selection process has resulted into disappearance of organisms that appear to be less adapted to the environment. According to Darwin’s theory, natural selection requires the behavior patterns reinforcement (Curtis and Barnes, 1989). The ecological approach to the animal behavior concerns the issues of natural selection, which involves the natural observation of the animal behavior. Ethology differs from the psychological and social science approaches by its oriented theoretical aspect described by Tinbergen (1663) using the four different explanations. The natural selection is described in the following explanations.
1. Functional Explanation of Natural Selection
The natural selection focuses on the competition for the resources. However, the protective adaptation concerns the attacks by same species or predator (Archer, 1988). The principle of evolutionary functional analysis is applied in the competitive aggression. For example, Brown (1964) states that the territorial defense would only occur if the benefits such as food and mate exceed the costs of fighting and patrolling of the area.
The sex differences can be understood from an evolutionary perspective of cost benefit. The differences include the size of the individual, muscular development, and longevity. They are consistent with the degree of sexual selection (Darwin, 1871, 1859). The differences in size and strength accompany the aggression (Archer, 2004). Escalated forms of aggression leading to homicide are the largest sex difference (Daly & Wilson, 1990).
2. Phylogenetic Origin of Aggression
The second of Tinbergen's four explanations, phylogenetic origins, is closely associated with the evolutionary function. When the bene%uFB01ts of engaging in a physical aggression increase, it indicates that a certain form of aggression has evolved. Therefore, aggression is observed in the animal kingdom (Huntingford & Turner, 1987). Some aspects of aggression are noteworthy from the point of view of zoological comparison. They concern the brain’s mechanisms of expression and inhibition of the organisms’ aggression. It involves expression of emotions associated with direct aggression. The aggressive behavior of organisms such as sea anemones, sedentary mollusks and corals shows low levels of neural organization (Archer, 1988, p.18–19). Thus, their brains do not fulfill the requirement for the physical aggression. However, human aggression is controlled by a brain mechanism.
3. Development of the Selection Origins
Acceptance of the aggression is the consequence of natural selection. It has implications for the consideration of the development. Conventional psychologists have been interested in its development, but largely from a no-evolutionary perspective. The emphasis has been made on the effects of social learning in social development explanation (Pinker, 2002). Thus, aggression is a behavior that is learned throughout childhood (Bandura, 1973; Lefkowitz, Eron, Walder, & Huesmann, 1977).
4. The Motivation of Aggression
Approaching the aggressive motivation from the viewpoint of functional evolutionary, the question of what problem the system is designed to solve is asked. For instance, an approach used by North American evolutionary psychologists listed the speci%uFB01c adaptive functions fulfilling the aggression, and suggested speci%uFB01c mental modules for each function (Buss & Shackelford, 1997). As indicated earlier, the functions of aggression falls under two main categories: reaction to the localized danger, and competition for the available resource (Archer, 1988). In%uFB02exible mechanisms are simply the re%uFB02ex-like responses to stimuli. They include the initiation of territorial aggression by simple stimuli and termed social releasers, such as the red breast of a robin (Lack, 1939).
Sexual selection is an adaptive change caused by the ability to obtain mates and reproduce. Darwin introduced the idea of sexual selection (Darwin, 1871). A number of males species display attractive traits and this dramatically reduces their survival ability compared to females’, intrigued Darwin. Survival capabilities become useful since they promote reproduction. Reproduction requires the organisms to attract their mates. Males having the desired features are able to fight other males and to win females. Conflicting with natural selection, sexual selection is a force of evolutionary change, particularly change in reproductive behavior.
The distinction of proximate and ultimate functions follows directly from the theory of natural selection. Sociobiology emphasizes the evolutionary biology in order to explain the social behavior of animals. The purpose of sociobiology is to explore the principles of evolution and behavior. Perhaps, they can assist in human behavior explanation.
Evolutionary psychology approach emphasizes the behavior as a function of psychological mechanisms that require input for activation. It is related to success in the survival and reproduction. Thus, psychological mechanisms are the product of evolution. The core issue for evolutionary psychologists is the nature of psychological mechanisms occurred as a result of selection and adaptation. Psychology of evolution can apply to cognitive and personality psychologies. Despite being criticized, evolutionary psychologists believe that their approaches will provide the needed integration of the disparate areas of psychology.