"A newborn's hands tend to be held closed, but if the area
between the thumb and forefinger is stroked, the hand clenches it and holds on
with sufficient strength to support the baby's weight if both hands are
grasping. This innate "grasp reflex" serves no purpose in the human
infant but was crucial in the last prehuman phase of evolution when the infant
had to cling to its mother's hair."
"If a baby is dropped, an immediate change from the usual
curled posture occurs, as all four extremities are flung out in extension. The
"startle reflex," or "embrace reflex," probably once served
to help a simian mother catch a falling infant by causing it to spread out as
fully as possible."
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