We may not be aware, but some unanswered questions remain dormant in our mind. Then sometimes while reading a book or listening to some person they pop up with answers. We get excited.
Long back while we were discussing natural selection and evolution. A question popped up. While the infants of other mammals are able to arrange their food by themselves after weaning, the human child is dependent on its parents for food and guidance for several years after weaning. Without prolonged parental care a human infant has practically no probability of survival.
Human child takes more than a year even to gain control over the movements of its limbs. Even after that it needs care, training, education and monitoring for nearly two decades or even more. This period has increased even further with advances in education. technology and culture. Tool based complex system of obtaining food does not allow human child the ability to gather food for quite some time. Ideally this should not have happened in the course of evolution. How to reconcile the paradox?
I asked my friends, students and colleagues. They were as much baffled by the query as me. It has stayed with me for so many years.
Thereafter I happened to read a book, which suggested that it is the helplessness of human baby that triggered the origin and evolution of family and society.
Ensuring reproductive success is the motivation of an organism. Reproductive success means the perpetuation of its genes in the next generation. To ensure transfer and perpetuation of its genes in the next generation parents have to take prolonged and intense care of the child. So parental care is of utmost importance. Need for intense and prolonged parenting is a hallmark of human life.
For the father it requires close cooperation with the mother. A mother may be confident that she is rearing her own child, but the father does not have that assurance. By closely cooperating with his partner he ensures the transfer of his genes to the next generation. That lays the foundation of a close and prolonged man-woman relationship, core of the institution of family.
Another human hallmark came to attention. Animals other than human beings die soon after the expiry of their reproductive age, but human beings have a prolonged longevity. Extended longevity makes prolonged parental care possible.
But I had still to wait for knowing as to why natural selection caused the helplessness of human child.
After good many years another book came to my attention.
The skeleton of our primate ancestors supported a creature that walked on all fours and had a relatively small head. Adjusting to an upright position was quite a challenge, especially when the torso had to support an extra large head. Humankind paid for its lofty vision and industrious hands with back aches and stiff necks.
Women paid extra. An upright gait required narrower hips constricting the birth canal – and this when the heads of babies were getting bigger and bigger. Death in childbirth became a major hazard for human females. Women who gave birth earlier, when the infant’s head were still relatively small and supple, fared better and lived to have more children. Natural selection consequently favoured earlier births. And indeed, compared to other animals, humans are born prematurely when many of their vital systems are still underdeveloped. A colt can trot shortly after birth; a kitten leaves its mother to forage on its own when it is just a few weeks old. human babies are helpless dependent for many years on their elders for sustenance, protection and education.
This fact has contributed greatly both to humankind’s extraordinary social abilities and to its unique social problems. Lone mothers could hardly forage enough food for their offspring and themselves with needy children in tow. Raising children required constant help from other family members and neighbours. It takes a tribe to raise a human. Evolution thus favoured those capable of forming strong social ties. In addition since human are born underdeveloped, they can be educated and socialised to a far greater extent than any other animal.
To conclude, it may be mentioned that with revolutionary achievements of human society in health care and other parameters, longevity has improved dramatically. Longevity is no longer linked with parental care.