Tuesday, May 10, 2016

From Life to Humans in Ten Commitments

When life first formed, a little less than four billion years ago, it only formed because it first made the commitment to multiply. This may remind you of a certain book, but unlike the account in the Bible, this form of life we now call Bacteria.  Bacteria and their allies are single celled organisms that multiply by splitting into identical copies of themselves.   

One and a half billion years ago is our next milestone, when plants and animals become separate creatures and both abandon splitting in favour of  commitment to sexual reproduction.  Lets call this the Sexual Reproductive System,later to become - “the birds and the bees and the flowers and the trees.”  

 As for us animals, unlike most plants,  we commit to eating Food and this leads to both the Digestive System and the Predator/Prey System
Food is important to this story and we will visit it again when we get to Cooking  But, for now, let’s note that ever since it came into being, the Predator/Prey System is one of the main drivers of evolutionary change.  

Nothing much happens for one and a quarter billion years, and then 250 million years ago smallish creatures that we call the first mammals arrive.  The mothers of these furry little critters stop laying eggs and instead give birth live.  These mothers commit to the care, protection,  and feeding of their infants.  Baby mammals are warm and cuddly and they cry when they are in distress.  Baby snakes and lizards are not so cuddly and they are silent, because nobody is going to protect them once they’re out of the egg.  

The Maternal Caring System  is a very important player in this story as I hope to make apparent to you. Mammal mothers have mammary glands that produce milk.  The hormones that are involved in the release of milk - prolactin and oxytocin are triggered by close physical contact between mother and baby.  These hormones contribute to the sense of pleasure and attachment between babe and mom.  

The close contact, the period of helpless infancy, the attachment bond between mother and child - these are all important, because they will help facilitate development outside the womb, making possible larger brains, greater learning capacity, and more behavioural flexibility than would ever be possible by a creature that comes out of an egg.  

The next commitment that mammals make is to the group.  Growing up and living in a group helps protect individuals from predators, and, just like having a mother, it makes longer infancies and more social learning possible.

65 million years ago a group of mammals called primates committed to living in trees.  Why live in trees?  To get away from predators and to facilitate access to fruits and other goodies.  By living in trees, primates, such as monkeys, evolved better hand-eye coordination compared to other mammals and this will be important when we get  to tools

20 million years ago Apes have evolved from monkeys.  Apes are bigger and stronger than monkeys.  Male apes are noted for being committed to the collective defence of the group against predators like boa constrictors and big cats, and to male outsiders.

About six million years ago our ancestors broke with the trees and committed to standing on their own two feet.  Being primates they had already benefited from improved hand-eye coordination,  so it wasn’t long before they learned to walk long distances, and then to make stone knives, and axes.

Now, you may or may not have noticed that for the last 250 million years, all this time that mothers were caring for their infants, there is little or no evidence of fathers’ commitment to care.   2 million years ago this would all change when the first humans - homo erectus come on the scene.  And here’s why:

Do you remember those maternal hormones that worked so well to create a mother child bond - prolactin and oxytocin?  These are produced in male bodies as well, because males and females share most of the same genetic material.  And you may have noticed that humans don’t have nearly as much body hair as apes.  In fact, without clothes we look pretty naked.

 Anyway, my point is that skin-to-skin contact can lead to the release of oxytocin in both males and females and this can facilitate falling in love and pair bonding.  Pair bonding is rare in primates, and doesn’t happen when apes live in groups.  It is usually prevented by the dominant male who will try to monopolize all the females.  

Homo Erectus, our hominin precursors, looked a lot more like us then previous hominins.  It was during their two million year stay on Earth that they were the first to control fire, and the first to walk out of Africa.

Remember those stone tools we talked about.  They were first used for preparing food, just as knives are today.  They were also used as weapons.  And here’s where it gets interesting. We note, that in human history, when better weapons are first developed they sometimes have a powerful effect on social systems. 

 Stone knives  would have had a leveling influence, undermining the rule of the strongest male. They would also have led to social disruption, because now there  would be a continual free fight over women. Previously the dominant male would have controlled this problem, but stone knives may have eliminated his role.

Easy access to knives would have made it a free-for-all until the group as a whole agreed to a system that limited violence and provided stability.  That agreement was the basis for human nature.

 Two million years ago agreements were not about peace, order, and good government.  The agreement had to be simple, it had to be comprehensive, with no exceptions, and it probably had to do with access to females.  Our ancestors had the right hormones to facilitate pair-bonding, but they didn’t have the right social systems until the invention of stone knives forced their hands.

 Because the dominant male kept order,  that function needed to be filled by something else.  That function, of allocating women and resources,and controlling violent behaviour, had to be replaced by a special type of collective commitment.

Today, in almost every human society most men and women live in monogamous relationships, which means that somehow, and I think it was two million years ago, we established  monogamous social systems.  Thus males and females committed to living in and supporting long-term relationships.

Animals do most things from self-interest. Humans choose to follow rules that can directly oppose their own self-interest.   This is most obvious in morality.  In morality we have lists of dos and don’ts.  We all internalize these rules and we often judge those who break them harshly. Justifying your behaviour by saying that you acted in your own interest doesn’t cut it morally.  Everyone is on the lookout for people who violate moral rules, and if they are  caught, they are punished.

We all can and do feel judgmental about people who have affairs. We realize that they are doing it out of powerful desires, but judge these people for not constraining their desires. The fact is that if people didn't actively constrain themselves, monogamy would be a joke. The only thing natural about monogamy is that it reflects the pair-bond, the deep mutual attachment that can form when two people fall in love. But the trouble is that, in many cases, love doesn't last, and it can be overridden by new attractions. That's why the group had to come together and make a collective commitment, simultaneously creating the social institution of monogamy and the first moral system. My guess is that initially it was simply an agreement to control violence, and allow for pair-bonding and social stability, and the initiators had no idea of the positive consequences that would ensue.

In a single stroke monogamy would have led to fathers being more assured of the paternity of their children, the inclusion of in-laws, and thus, the effective enlargement of groups, the division of labour between males and females, and the sharing of resources amongst the nuclear family.  In effect, monogamy led to camp fires, cooking, and fatherhood.

At some unknown time, perhaps 100,000 years ago, by increasing social stability and encouraging sharing, monogamy made language, the tenth commitment, possible.

Female mammals committed to maternal care; most mammals committed to living in groups; male baboons and apes committed to collective protection of the group; humans first committed to a monogamous social system and then committed to using language.  The trend in all of these commitments is towards the facilitation of longer childhoods, greater learning flexibility, bigger brains,  and more effective and complex forms of cooperation.  Humans have the longest period of childhood, the greatest ability to learn new things, and are by far the most cooperative.  

Remember the camp fire:  Sharing stories, sharing food, singing songs together, facing the darkness together.  Almost everything we do as humans involves sharing: talking, singing, eating, playing, working, building, caring, and loving.  This is what separates us from the animals.