How Babies Sleep: A Science-Based Guide to the First 365 Days and Nights

by Helen L. Ball

But human babies are also the most neurologically undeveloped of all primates at birth,13 lacking the muscle tone and neuromuscular coordination to either cling to their mother or run after her for months, never mind within hours of birth. So, our babies are precocial in most respects but are unusually helpless due to their lack of strength and coordination, unable to maintain close contact with their mother without help—a situation that makes human babies both unique and uniquely vulnerable.14 Evolutionary anthropologist Karen Rosenberg observed that the helplessness of human babies in comparison with other primate species was not recognized by zoologists and anthropologists until the middle of the twentieth century, and this has since developed into a gradual understanding that our slow and prolonged childhood development is a key aspect of our biology that differentiates us from other species.15