When a newborn’s inner foot sole is stroked , the toes curl around (“grasp“) examiner’s finger. Baby: 2½ weeks old. The reaction is present in babies at birth but should disappear after 6 - 12 weeks. For some this baby reaction supports the idea that long ago humans lived in trees. But this is scientifically not justified, read the description box of my vid on the Babinski reflex.
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