Resumen
Adaptation: a change in the structure or functioning of an organism that makes it better suited to its environment (i.e., a heritable characteristic that tends to increase the fitness of individuals possessing it).Adaptive: tending to increase the individual's fitness (i.e., conferring an advantage in terms of survival and reproduction).Note: any adaptation was, necessarily, adaptive at some point in an organism's evolutionary history, but changes in environment or ecological niche can reduce the benefits of a formerly advantageous adaptation.Alloparent: an individual other than a biological parent who helps to care for juveniles.Altruism: helping behavior provided at a cost to the performer (See also Selfishness.)Coefficient of relatedness: the percentage of genes, on average, that two individuals share by common descent.The coefficient of relatedness between parent and child, or between full siblings, is .5 (i.e., they share one-half of their genes).That between aunts or uncles and nephews or nieces, or between grandparent and grandchild, is .25 (they share one-fourth of their genes).Fitness: the reproductive success of an individual, commonly expressed in terms of the number of copies of his or her genes an individual succeeds in getting into the next generation.Direct fitness: success resulting from the individual's personal reproductive efforts.Indirect fitness: success resulting from the reproductive efforts of relatives with whom the focal individual shares genes, weighted according to coefficients of relatedness to the focal individual. Inclusive fitness:The sum of an individual's direct and indirect reproductive success.(i.e., personal reproductive efforts and reproductive efforts of kin).Genotype: the genetic constitution of an individual organism, i.e., the organism's full hereditary information.(See also Phenotype.)ix Glossary Hypergamy: marrying someone superior to oneself, typically measured by social status or material wealth.Hypogamy: marrying someone inferior to oneself, typically measured by social status or material wealth.Intersexual: between or among members of the opposite sex (i.e., intersexual conflict = conflict between men and women).Intrasexual: between or among members of the same sex.Kin selection: selection for genes causing individuals to favor close kin (i.e., selection for behaviors that increase the inclusive fitness of the performer).Nepotism: any discriminative behavior tending to favor an individual's relatives and hence to contribute to that individual's inclusive fitness.Parental investment: any investment by a parent in an individual offspring that increases the offspring's chance of surviving (and of future reproductive success) at the cost of parental ability to invest elsewhere.Phenotype: the manifest nature of an organism, including morphological, physiological, and behavioral attributes.(See also Genotype.)Proximate cause of behavior: the internal reinforcing mechanism (e.g., hormonal or psychological) that triggers a behavior.(See also Ultimate cause.)Reproductive value: an individual organism's expected future contribution to its own fitness.Residual reproductive value: an individual's remaining reproductive value, as measured at a given point in time, taking into consideration age, sex, health, environmental conditions, and other pertinent factors.Selfishness: behavior directed toward maximizing the survival and reproductive success of the performer.(See also Altruism.)Strategy: a blind, unconscious behavior program.Ultimate cause of behavior: the reason why a specific reinforcing mechanism (i.e., the proximate cause) evolved; that is, the survival-oriented or reproductive purpose it serves.(See also Proximate cause.)
