Pregnancy & Baby
By Yvette O'Dowd
H
ave you ever held a young baby and touched the palm of their hand with the length of your finger? If that baby was neurologically typical, I’ll bet those little fingers tightly grasped hold of your finger like their life depended on it.
This action is known as the Palmar reflex and once, very long ago, the life of an infant did depend upon it working. You’ll see a similar response from those tiny toes if you tuck your finger underneath them too: they curl in an attempt to hold on. The secret purpose of this reflex is revealed when you watch other primate mothers with their young: the Palmar reflex is how the infant holds on to its mother as she moves about the forest foraging for food, creating a night nest or following the nomadic pathway of the troop. This vestigial reflex, remaining long after humans evolved to become (mostly) hairless has always fascinated me. Because it gives insight into the origins of baby carrying - crucial in a species born so incredibly immature as homo sapiens. 94
Peninsula Kids – Autumn 2018
Evolution of Man as hunter-gather meant our males needed to become swift as they hunted prey large enough to meet the needs of their tribe. Running while covered in thick hair in hot climates such as what we now call Africa was not efficient, so over time, hair became shorter and finer: it aided evaporation of sweat, keeping the runner cool as he covered long distances. But the female also became increasingly hairless, posing quite a problem for mothers. With dependent infants unable to walk for a full year after birth and not able to keep up with the nomadic tribe on foot for 3-4 years, a hairless female could no longer rely on the infant clinging to her chest or back. This forced her to use her hands and arms to support her young, making her unable to forage for or carry food. It was not practical to lay the baby on the ground while she worked. She could cover a large area of ground as she collected seasonal fruits, tubers and other edible plants. Leaving her infant unattended put it at risk of predators seeking out the young and the weak. Attracting predators by crying put the whole tribe at risk. Additionally, the tribe travelled