Daniel G. Freedman
As I listened to Dr. Zelazo presentation, I was immediately struck with its importance. Has anyone before demonstrated the continuity over the first year of a newborn reflex? Even if this is not a first, I am still amazed.
The fallout of this finding has hardly begun. Zelazo himself has some speculations, but I consider them rather weak. For example, he takes Super's remarks seriously and suggests that the advanced motor milestones seen in Kipsigis babies result from parental practice. However, it is well known by now that newborn and neonatal Black African infants of many different African tribes, as well as Afro-Americans, evidence motor precocity ( Freedman, 1974; Leidcrman, Babu, Dagia, Kraemer, & Leiderman, 1973; Warren, 1972) and it seems most likely that we are witnessing the results of differences in gene pools rather than in parental practices ( Freedman, 1974). Additionally, among the Hausa of Nigeria, where I did some work, primary responsibility for rearing the youngest usually lies with an older sibling who for the most part carries the baby about on a sling; as far as I could observe, the babies there do not get special practice, yet motor precocity characterizes this group, too ( Freedman , 1974).
Interestingly, Zelazo mentions that Yucatecan infants are also carried on a sling. However, here the fact of being carried about is used to explain late walking among this American Indian people. The gene-pool explanation seems applicable here, too, when one considers the data of Dennis ( 1940), who obtained the only other norms on walking among Indians. He found that the Hopi of Arizona also walked late (approximately 13 months) whether or not they were raised on a cradleboard. Our own data on the Navajo, now being gathered, indicate a similar