Can knowledge of developmental processes illuminate the evolution of parental care?

Abstract

There are two levels of investigation for elucidating the evolution of parental behavior. The macro level focuses on how parental behavior can evolve as an aspect of reproduction. The micro level focuses on how species variations in parental behavior evolve. Recently, modern evolutionary biology has turned to developmental biology as a source for information about how trait variability (the substrate upon which natural selection and other evolutionary mechanisms can operate) can emerge during development (called ''evo-devo''). Application of this evo-devo approach to the phenomenon of parental behavior requires identification of those mechanisms that produce variations in developmental pathways leading to parental behavior. It is these variations that provide the phenotypes for the potential evolution of different parental behavior systems. Variations in rodent maternal behavior affect the development of the HPA and HPG axes in their offspring. These mechanisms are examined to reveal how such developmental variations could underlie the evolution of biparental behavior. Knowledge of the developmental mechanisms responsible for species variations in mammalian parental behavior systems may provide insight into those mechanisms that may have been involved in the evolution of parental behavior itself. ß 2006 Wiley Periodicals, Inc. Dev Psychobiol 49: 33-44, 2007.

Variations in maternal care alter corticosterone and 17beta-estradiol levels, estrous cycle and folliculogenesis and stimulate the expression of estrogen receptors alpha and beta in the ovaries of UCh rats

“…After birth, essential hormones, such as prolactin, oxytocin, estrogen and corticosterone may be associated with maternal interaction [9-11], behavioral and hormonal changes stimulate the female to protect their litters [12,13]. However, once the mother-pup relationship is established, the pup's activities signal to the mother to stimulate maternal care.…”

The Roles of Environment, Experience, and Learning in Behavioral Development

“…The substances leaked or secreted through the membranes of the daughter cells contribute to the environment of each other. Variability in the spatial landscape of the cells, as they divide, also contributes to their variability in the secretions they produce as environments for neighboring cells and in their responsiveness to the secretions of their neighbors (c.f., Michel & Tyler, 2007a).…”

“…If experience maintains a trait beyond the developmental phase in which it may be most appropriate, the trait could become an important exaptation for the emergence of a new species. For example, juvenile males in many species of rodent exhibit alloparental care of pups (Michel & Tyler, 2007a). Such parental behavior disappears after puberty (adult males of many species kill pups and hence most rodents are uniparental).…”

“…There are several experiential conditions (specific circadian light and/or temperature conditions) that seem to maintain the male's alloparental care into adulthood. These experiential conditions (which are associated with particular habitats) may have been the foundation for the evolution of biparental care in certain rodent species (Michel & Tyler, 2007a). Maintaining experiences can be a necessary condition for the development of many other features.…”

Behavioral science, engineering, and poetry revisited.

“…There are species of rodent (e.g., CA mouse, (Peromyscus californicus) prairie vole) and monkey (e.g., marmosets) in which the male parent contributes to the care of the offspring. Examination of these species has begun to alter our understanding of the parental factors affecting offspring development ( Michel & Tyler, 2007). Human play behavior may be understood from the natural history orientation ( Burghardt, 2005).…”