Steven Pinker on Emotions and Genes

Steven Pinker’s How the Mind Works might well be subtitled “And the emotions too.” It’s one terrific book. It offers a barrage of insights and connections about humans and evolution that can feel intoxicating. It stirs up the nature-nurture controversy with a blender. It does not see you as you almost certainly see yourself. And it is often very funny.

Despite the book’s title, Pinker talks more about emotions than about the mind itself. He sees them working together. The mind, he says, is computational: it processes information. Much of this information comes from the body’s biological systems. Emotions are units, modules, that use this bodily information to take direct steps—fear, anger, hunger, lust, egotism, empathy—that will promote survival and reproduction.

Humans, Pinker writes, are not, as we often believe, divided into thoughts and feelings that work against each other.

The emotions are adaptations, well-engineered software modules that work in harmony with the intellect and are indispensable to the functioning of the whole mind. The problem with the emotions is not that they are untamed forces or vestiges of our animal past; it is that they were designed to propagate copies of the genes that built them rather than to promote happiness, wisdom, or moral values. We often call an act ‘emotional’ when it is harmful to the social group, damaging to the actor’s happiness in the long run, uncontrollable and impervious to persuasion, or a product of self-delusion. Sad to say, these outcomes are not malfunctions but precisely what we would expect from well-engineered emotions. (Kindle location 7688)

So the good news is that our seemingly perverse emotional moments do not mean that something is wrong with us. But the not-so-good news is that our emotional acts are more deeply engrained in us than our well-meaning searches for happiness, wisdom, and virtue.

So are we doomed by the genes that build these emotional responses, responses that often mean we get  carried away just when we want to stay cool and collected? Pinker addresses this issue often, here in a discussion of love:

The confusion comes from thinking of people’s genes as their true self, and the motives of their genes as their deepest, truest, unconscious motives. From there it’s easy to draw the cynical and incorrect moral that all love is hypocritical. That confuses the real motives of the person with the metaphorical motives of the genes. Genes are not puppetmasters; they acted as the recipe for making the brain and body and then got out of the way. (8342)

I like the recipe metaphor. As I take it, genes are like the list of the ingredients and the steps for making a cake, but the flavor and texture of the cake itself is quite different from that sheet of instructions.

A human

A human “cake” and his genetic “recipe”
(images.nationalgeographic.com)

But if the genes have built emotions to keep us alive, doesn’t that mean those emotions are quite inflexible? Yes and no. Our own emotional core might not change much in our life time, but in species-time, the story is different.

Might the software for the emotions be burned so deeply into the brain that organisms are condemned to feel as their remote ancestors did? The evidence says no; the emotions are easy to reprogram. Emotional repertoires vary wildly among animals depending on their species, sex, and age. Within the mammals we find the lion and lamb. Even within dogs (a single species) a few millennia of selective breeding have given us pit bulls and Saint Bernards. (7721)

Pinker, in conclusion, tells us about ourselves in ways we may have difficulty recognizing. Modules and systems fine-tuned to an ancient past may seem non-human and even anti-human. But it’s not so difficult to absorb how science depicts the machinery of our emotions at the same time that we are inquiring thoughtfully about the meanings of our lives. Or, to put it another way, we can come to understand our recipe while we ponder what it is like to be the cake.

For more on the man, the book, and the debate, here is a lively and helpful article.

Genesis for Non-Theists

Creation narratives are lively stories.  In the Bible, God creates the universe and earth in six days. In other traditions, creatures are dismembered, huge eggs hatch, birds create land. Even science’s own creation narrative starts with a Bang and once earth takes shape, the first organic molecules appear relatively quickly, within a billion years. 
 
But at that point the scientific story of life slows way down. Life remains at the stage of single cells for the next two billion years. What was happening to our smallest, oldest ancestors all that time? Why did it take so long to move beyond the stage of one-only? Was evolution on hold?
timeline

From “Oldest bacteria fossils” to “Multi-cellular eukaryotes” 2 billion years later, life on earth was single-celled.
(vector-clip-art.com)

What took so long was the creation of the building blocks for being alive. It’s a story with parallels to the first chapters of Genesis. The biblical sequence: plant life emerges on the third day, including “fruit trees bearing fruit in which is their seed,” followed over the next three days by creatures of the water, air, and land, including man and woman. A few verses later we read about the Garden of Eden and, symbolically, the beginnings of sex and death.

Here briefly is science’s version: life evolved from the simplest cells to cells with a nucleus that enclosed the protected “seed” of DNA. This change set in motion the end of one kind of immortality, the beginnings of sex and death, and the emergence of a new immortality.

The process was slow because the changes were huge.

LUCA
Like the Bible, science has a name for our first ancestor. LUCA, our “last universal common ancestor,” was a single-celled organism, a kind of bacterium, from which all life on earth is descended. Inside LUCA was a floating coil of DNA, sections of which have been passed down to every living thing.
Prokaryote

Our common ancestor, a cell with DNA but no nucleus
(shmoop.com)

LUCA reproduced simply by dividing, with one set of genes in each new cell. The new cells were identical, a long line of Adam clones without an Eve.

LUCA’s membrane enclosed only watery liquid and the genes. Gradually LUCA’s descendants “ate” and absorbed other bacteria. Some of these bacteria turned into the nucleus of the cell that absorbed them. They became the container for the cell’s genes. Such cells advanced from  prokaryotes (before a nucleus) to eukaryotes (a true nucleus, and pronounced “you carry oats”). The nucleus was a seed, a seed that provided the DNA with a chemical environment of its own and helped grow more complex DNA and much larger cells.
Sex, Death…
cell

Cells get a nucleus–and more.
(biogeonerd.blogspot.com)

Early cells were, in their own way, immortal. The genes in both prokaryotes and early eukaryotes would reproduce and then the cell would split into two identical cells, as bacteria still do. Did such cells die? Eventually, but only from accident or the environment. In this Eden, cells did not get older. They became their own offspring and could theoretically live forever.

Eukaryotes, however, found a new way to reproduce. One would rub up against another eukaryote and portions of their DNA sets would be inserted into the other—the original sex act. With this exchange of DNA, genetic variation sped up, at last. So did natural selection.
 
In the next step, sex became specialized. As some early organisms became multi-celled, such as algae, they reproduced not by division of the whole parent organism but, as with us, by means of specialized germ cells (not the disease kind of germ but the creative kind, as in the “germ of an idea”).
No longer was the parent reincarnated in a clone, as in bacteria. It was left behind, and it aged and died. As in Genesis, the co-mingling of different living things brought sex and death. Cellular life moved beyond Eden.
 
…and Immortality
So we have lost the immortality that the prokaryotes enjoyed. But we have found it in another, more complex form. Our immortality runs through the genetic line of our children and other blood  relatives. It turns out that it is not the body, the soma, that is the crucial package. It is the germ cells that carry the DNA forward. 
 
But is this an adequate and satisfying idea for us humans who dream of living forever? Is the continuity of DNA a meaningful form of immortality? Here is one answer from Harvard biology professor George Wald, in his 1970 lecture on “The Origins of Death.”
 
We already have immortality, but in the wrong place. We have it in the germ plasm; we want it in the soma, in the body. We have fallen in love with the body. That’s that thing that looks back at us from the mirror. That’s the repository of that lovely identity that you keep chasing all your life. And as for that potentially immortal germ plasm, where that is one hundred years, one thousand years, ten thousand years hence, hardly interests us.
 
I used to think that way, too, but I don’t any longer. You see, every creature alive on the earth today represents an unbroken line of life that stretches back to the first primitive organisms to appear on this planet; that is about three billion years. That really is immortality. For if the line of life had ever been broken, how could we be here? All that time, our germ plasm has been living the life of those single celled creatures, the protozoa, reproducing by simple division, and occasionally going through the process of syngamy — the fusion of two cells to form one — in the act of sexual reproduction. All that time, that germ plasm has been making bodies and casting them off in the act of dying. If the germ plasm wants to swim in the ocean, it makes itself a fish; if the germ plasm wants to fly in the air, it makes itself a bird. If it wants to go to Harvard, it makes itself a man. The strangest thing of all is that the germ plasm that we carry around within us has done all those things. …
I, too, used to think that we had our immortality in the wrong place, but I don’t think so any longer. I think it’s in the right place. I think that is the only kind of immortality worth having — and we have it.

My Genome and Me

Recently I sent a DNA sample on two Q-tips swabbed inside my mouth to the National Geographic genome project. The information I received back described the whereabouts of my ancestors over the last 50,000 years or so. I’d known bits and pieces about my parents’ parents, all from different parts of Europe. But the DNA analysis showed me when their own early ancestors came to Europe out of Africa and what groups they belonged to when they got there.

Long before their journey, about 2 million years ago, earlier human species began migrating from Africa. Then about 60,000 years ago Homo sapiens began crossing Egypt and the Arabian peninsula. When we got to Europe, our cousins the Neanderthals were settled there and we settled down with them. Really, with them. My genetic make-up is 1.1% Neanderthal, which is the average for modern day non-Africans.

(crystallines.com)

(crystallines.com)

The genome report goes on to describe the two particular migrations on my mother’s and father’s sides out of Africa. On my father’s side, Branch H5 spread into Central Asia to points east and west, around 10,000 years ago. Today, H5 genes are common around the Black Sea and less so throughout Europe. Viking King Sven Estridsen, born in England but king of Denmark from 1047 to 1074, belonged to this group. He may have been one of my ancestors, but more likely he collected tribute from them.

On my mother’s side, Branch L2, about which less is known, left their genetic marker most frequently in Algeria, in northern Africa, but also in Asia and Europe, routes indicated quite clearly on the inset map.

Finally, there is my more recent regional ancestry, the combined information about both parents connecting me to any of 18 population groups around the world six or more generations ago. My genome links to three such groups. Forty-one percent of my DNA is descended from the Jewish Diaspora, the dispersal of Jews from the Near East, in this case into Europe. Thirty-one percent comes from Southern Europeans, the original peoples of the northern Mediterranean Coast. Finaly, 28% comes from Scandinavians, the most recent of the groups, since that area was peopled only after its glaciers melted around 12,000 years ago.

I’ve shared these results with family and friends, with mixed responses. Some find them too general to mean much. But they’ve also set off alarms about the pitfalls of knowing such information—about oneself or about others. The percentages and group identities make it tempting to imagine that a person is the way he or she is because of his or her ancestry—that I’m studious, for example, because of Jewish ancestry. A TV commercial shows a man who enjoys Swiss dances and lederhosen and who then finds from his genome that he is Scots, so he quits the lederhosen and takes up kilts. As if his genes made him suited for one but not the other. Did he feel it would be inappropriate or hypocritical to continue in the lederhosen? That seems not just silly but a little frightening. His genes are not him, not his abilities, not his interests.

True, some physical features, some potential abilities, and predispositions to some diseases are inherited. But our specific and individual characteristics depend as much if not more on the web of family, community, and culture and the flux of time. Saying a person has a specific characteristic because of his ancestral group is a shade less inaccurate than saying he has it because of his astrological sign.

For me, the genome history helps fill in my reveries about ancestors leading their particular lives a very long time ago. I picture a family walking in Eastern Europe, another farming in Italy, or a group crossing the water from Denmark, none of them knowing that far in the future, the paths of their descendants will come together in me. I imagine myself greeting them from their future and watching their surprised smiles as they realize who I am and as I tell them how often I’ve been thinking of them.