Mother-Infant Relationship in Galagos and the Oral Child-Transport Among Primates

Abstract

The maternal child-transport in the lorisiform G. senegalensis bradfieldi and G. crassicaudatus monterii and the early behavior patterns of the infants are described and compared. The studies include observations of both wild and captive animals. The carrying of the infant in the teeth of its mother, or of another female acting as midwife (G. senegalesis), was the specific mode of child-transportation in both species. Maternal carrying-behavior and its functional significance are influenced in the 2 species by their different ontogenetic patterns. These are defined in terms of developmental stages of the neonates and by their rates of development. The neonate of the smaller G. senegalensis appeared less developed and showed a more prolonged dependency on this special maternal care than the larger G. crassicaudatus. Mouth-transport as established in galagos is discussed as a phylogenetically old behavior pattern which these species share with many nonprimate mammals. At present no phylogenetic lineage can be established either for this behavior nor for the primate species that now show it; the prosimian and 1 simian species known to show oral child-transport are mentioned. Judged by the characteristic correlation between mouth-transport and the specific development of the infants, one may envision its quick disappearance with the phylogenetic advancement of the primate ontogenetic pattern. The relevant phylogenetic trend characterized the nonhuman neonate as a dependent nidifugous organism. The prefection of the grasping abilities and establishment of fine control of the hand were both seen as important features influencing the change from oral child-transport to the clinging of the infant to the mother''s body. The study emphasized the need for a comprehensive comparative approach based on anatomy, physiology and ethology.