Resumen: En la presente tesis teórica se muestran las características que otras disciplinas ajenas a la Economía, principalmente la Antropología física y la Psicología evolucionista, han determinado como identificadoras del contexto en el que la motivación a cooperar surgió como rasgo adaptativo en los seres humanos, denominado a lo largo del texto Entorno Relacional de Homo sapiens (ERHs). Sobre estas bases, se propone un nuevo planteamiento teórico, la Frontera informal de los grupos humanos en las organizaciones, la estructura organizativa implícita a la que la predisposición conductual humana a cooperar se ha adaptado, y que sus integrantes determinan y evalúan constantemente, de manera no consciente. Cuando, en una organización, la totalidad de su estructura organizativa coincida con los caracteres de una Frontera informal, se favorecerán la aparición y el mantenimiento de conductas cooperativas entre sus miembros. Comparando los caracteres de la Frontera informal con las estructuras formales que generalmente gobiernan las organizaciones, será posible identificar aquellos aspectos en los que difieren, y en consecuencia, proponer cambios que faciliten la generalización de una motivación a cooperar.
Resumen (otro idioma): Cooperation among people is an adaptive trait, and as such, its motivation is innate; therefore, cooperate is a behavioural predisposition in humans. Different authors highlight that establishing an organizational context in line with the motivation to cooperate will make feasible for the interest of workers to side with the interest of their colleagues and the organization itself, as a mean for improving its functioning. This thesis is a theoretical work which explains the main characteristics identified by scientific disciplines not related with Economics, mainly Physical Anthropology and Evolutionary Psychology, as determining for the context in which the motivation to cooperate emerged as an adaptive trait in human beings, referred to in the text Relational Environment of Homo sapiens (REHs). According to the bases outlined in REHs, a new theoretical approach is proposed, the Informal boundary of human groups in organizations, that is the implicit organizational structure to which the human behavioural predisposition to cooperate has adapted, and which whose members determine and evaluate constantly in an unconscious way. When, in an organization, all its organizational structure fits in with the features of an Informal boundary, the emergence and maintenance of cooperative conducts among its members will be favoured. Comparing the features of the Informal boundary with the formal structures that usually govern organizations, it will be possible to identify those aspects in which they differ and, consequently, to propose changes that facilitate the generalization of a motivation to cooperate.