As demonstrated by Myrtle B. McGraw (1899-1988), human newborns show swimming-like patterns of movement (see figure below) reminiscent of the front and back crawl when placed faced down or supine in water, suggesting a strong and well-developed diving reflex in newborns. It also suggests that it is an ontogenetic adaptation to prenatal life in the amniotic fluid as, like newborn imitation and pre-reaching movements, it disappears in subsequent weeks.
