CHAPTER 4
LECTURE EXTENSION
Motor Development Among the Ache of Eastern ParaguayAn excellent example of the impact of culture on motor development comes from a study of young children among the Ache, a hunting-and-gathering society of Eastern Paraguay. Kaplan and Dove (1987) found that Ache children between the ages of 2 months and 4 years developed linguistic, fine motor, and gross motor skills at a slower rate than their American counterparts, with the greatest gap appearing in gross motor development. The delay was strongly related to age: Children under 1 year lagged 2 to 3 months behind American norms, and 3- to 4-year-olds lagged 17 months behind. Gradually, as Ache children enter middle childhood, the delay disappears. Older children have extremely well-developed motor skills.
Culture-specific child-rearing practices are probably responsible for these findings. Since the forests in which Ache live contain many hazards, parents are very reluctant to allow children under 2 years to explore freely. Children who are active and mobile at an early age are more likely to encounter poisonous snakes, insect pests, and parasites that spread infection. Consequently, mothers commonly pull children who begin to crawl out of reach back to their laps. Once Ache children begin to explore the environment, they do so very tentatively. They seem to have picked up the cultural desire that they remain close to their parents, refrain from investigating their surroundings, and acquire motor skills at a slower rate.
Heredity may also contribute to the slower motor development of Ache children. Since passive infants are more likely to survive in the dangerous Ache environment, perhaps genes that contribute to this temperamental style were more likely to be passed on to succeeding generations.
Kaplan, H., & Dove, H. (1987). Infant development among the Ache of Eastern Paraguay. , 23, 190-198.
LEARNING ACTIVITY
Recording Adults' Reactions to Infants' CriesAsk students to locate a mother and/or father of a young infant and enlist the parent's assistance in recording the baby's cries. Have students listen to the recordings and note their own reactions, describing the feelings the cries evoke and their interpretation of the meaning of each cry. Then have students play the recordings for two adults-one who is a parent and one who is not-and interview them about their reactions to the cries. Do the adults' responses agree with research in the textbook?
If students cannot obtain infant cry samples, the recordings of cries that accompany the monograph listed below can be used as the basis for this activity.
Wasz-Höckert, O., Lind, J., Vuorenkoski, V., Partanen, T., & Valanne, E. (1968). The infant cry: Aspectographic and auditory analysis (Clinics in Developmental Medicine No. 29). Suffolk, Eng.: Lavenham Press.