How Did Life Emerge from Stuff?

How, specifically, is a living thing different from lifeless chemistry? Once we can answer that question, we can ask the next one: How did the first emerge from the second?

Jeremy Sherman’s new book, Neither Ghost Nor Machine: The Emergence and Nature of Selves explains recent thinking on these questions, especially the work of neuroscientist Terrence Deacon. In this post and the next, I’ll summarize highlights of the book.

Sherman emphasizes this difference between living and non-living things: living things have purpose and non-living entities do not. Purpose here has little to do with what we mean when we talk about a person’s “sense of purpose” and it has nothing to do with divine intention. It refers instead to biological processes aimed at maintaining the state of being alive. The heart’s purpose—its function—is to pump blood. The purpose of a leaf is to produce food for the plant. We take for granted that bodies and their parts serve functions and yet it feels strange at first to identify purpose itself as a distinguishing feature of all organisms.

campfire (shutterstock.com)

shutterstock.com

Non-living stuff has no such purpose or aim or sustaining function. A fire in the fireplace burns and gives off heat and carbon and other gasses and then the fire, without more fuel, goes out. Sherman writes, “Most chemical reactions yield a proliferation of molecular products” but such reactions soon peter out. The reactions in living things, on the other hand, don’t fizzle out so easily. Through their biochemistry, living things “are self-regenerative in two senses: they maintain their own existence, and they produce new selves” (9).

Produce new selves? Sherman (like many biologists) refers to organisms as selves. Like purpose, applying self to an organism calls attention to the ways that even a bacterium, like a human, works to find food, defend its-self, repair its-self, and make more selves. Inanimate things don’t act as selves. Left alone long enough, anything inanimate will become disorganized and break down. An ice cube left on a counter will melt and then evaporate, its molecules finally dispersing into the air. And with selves, we can say that something—fuel, information, lower temperature—is good or bad or useful or significant for it. In contrast, as Sherman writes, “Nothing is ever functional, significant, or adaptive for sodium chloride, snowflakes, mountains, fried chicken, or even computers” (25).

But what about natural selection? Didn’t Darwin’s work explain how living things evolve? Yes, but natural selection doesn’t explain the first appearance of the selves that do the evolving. “To claim that natural selection explains purpose is like claiming that erosion explains mountains. Erosion…explains how mountains are passively sculpted, but not what’s sculpted. Likewise, natural selection explains how populations of selves are passively sculpted…[as] some lineages produce more offspring than others, but not how selves arise in the first place.” (9).

So, here’s the mystery: what kinds of inanimate chemical reactions might have come together as stepping-stones towards purposeful, self-regenerative selves? I’ll summarize Sherman’s answers in my next post.

“Damn it, it’s MY Body That’s at Stake”: Autonomy, Sociality, and Imperfect Choices

My family were swapping medical grievances one evening: flawed diagnoses, unwanted side effects, useless procedures. “Damn it, it’s my body that’s at stake” was one protest. As a species, we are quick to feel protective of more than just our health. Insert “my life,” “my rights,” “my money,” “my freedom.” When alarmed, we rush to defend our autonomy from relatives, employers, government, banks. Don’t tread on me.

But we work the other side of this interaction too. We uphold—because we benefit from— social codes and expectations against would-be rebels. “Don’t forget to invite that cousin you don’t like. Family first.” “You’re going to wear that?” “Showing up is eighty percent of the job.”

We carry both the autonomous nonconformist and the social enforcer inside us. The roles take different forms in different cultures, but they are in our genes. Our autonomy is our expectation that we can exist independently from others, that we can make our own decisions, solve problems ourselves. But that doesn’t mean we expect to go it alone. We are groupies, as contradictory as that seems to autonomy. The biological term is sociality. Sociality doesn’t refer to being sociable or friendly. It refers to the inherited tendency to form groups, sometimes highly organized groups. Social ants work for the queen, bees signal each other how to get to honey, wolves hunt in packs. Stronger together.

But as inherited traits, autonomy and sociality aren’t so perfect together. Most species inherit more of one than the other. Cats go solo, while ants hatch already equipped for their roles as workers, soldiers, or queens. The blessing and the curse for humans is that we have high levels of both. It feels right to us to decide what is best for our self—at the same time that we’re reluctant to risk our social support. The result is ambivalence. “Should I take the statin/invite the cousin/change my shirt/get my lazy self to work?”

Here, says sociobiologist Edward O. Wilson, is our spiritual turmoil and our humanity. When our loyalty to our clan, party, religion or other group clashes with our sense of our individual well-being, we feel angry, sad, confused, frightened, or betrayed. Near the close of the fifth chapter of Sociobiology (2000 edition), Wilson summarizes the dilemma with a passage from the Bhagavad Gita, the Hindu epic from 300 B.C. E. Here, the god Krishna steers the chariot of the reluctant prince Arjuna to an impending battle in which Arjuna’s relatives and closest friends will be fighting not with Arjuna but for the other side. Wilson writes about

ambivalence as a way of life in social creatures. Like Arjuna faltering on the Field of Righteousness, the individual is forced to make imperfect choices based on irreconcilable loyalties—between the “rights” and “duties” of self and those of family, tribe, and other units of selection, each of which evolves its own code of honor. No wonder the human spirit is in constant turmoil. Arjuna agonized, “Restless is the mind, O Krishna, turbulent, forceful, and stubborn.”

Krishna-Arjuna-battle (hinduhumanrights.info)

Arjuna hesitates on the Field of Righteousness (hinduhumanrights.info)

I first read that passage years ago but it comes back to me when I hear protests and arguments. We are Arjuna, come to the field of life with two strengths that work to our advantage but also get in each other’s way. I understand people better, myself included, when I listen for the rumbling, ageless tension of self versus group beneath our “imperfect choices” and “irreconcilable loyalties.”

Dawkins: Not One of Our Ancestors Was a Failure

Richard Dawkins’s theme is upbeat:

All organisms that have ever lived—every animal and plant, all bacteria and all fungi, every creeping thing, and all readers of this book—can look back at their ancestors and make the following proud claim: Not a single one of our ancestors died in infancy. They all reached adulthood, and every single one [allowing for the inclusion of such outliers as in vitro fertilization] was capable of finding at least one heterosexual partner and of successful copulation. Not a single one of our ancestors was felled by an enemy, or by a virus, or by a misjudged footstep on a cliff edge, before bringing at least one child into the world. Thousands of our ancestors’ contemporaries fail in all these respects, but not a single solitary one of our ancestors failed in any of them.…Since all organisms inherit all their genes from their ancestors, rather than from their ancestors’ unsuccessful contemporaries, all organisms tend to possess successful genes. They have what it takes to become ancestors—and that means to survive and reproduce…That is why birds are so good at flying, fish so good at swimming, monkeys so good at climbing, viruses so good at spreading. That is why we love life and love sex and love children. It is because we all, without a single exception, inherit all our genes from an unbroken line of successful ancestors. (River Out of Eden)

Many readers love this passage. Its any-organism’s view backwards along the unbroken line of forebears celebrates the successes and joys of being alive. And it explains this success not as the result of human uniqueness or a generous deity but as nature’ own selection process. The same pride and pleasure we take in hearing about a great-grandmother who struggled, travelled, settled, and raised a family, Dawkins extends to all ancestors of all species, without exception. Any reader who may have earlier viewed evolution as alien and godless might feel a little less resistance now.

But other readers may take exception to the passage for other reasons. Some of that inheritance from our successful ancestors, we wish we would be spared. Down Syndrome, Cystic Fibrosis, some cancers, and other diseases are inherited to a degree. So are mental illness and violent tendencies. For those suffering from such inheritances today, the genetic filter has not been effective enough.

And then there’s bad luck. Many organisms that were as well-endowed genetically as “successful” ancestors might also have left offspring had it not been for factors beyond their control. The twin of that pioneer grandmother may have died in battle, gone down with the ship, succumbed to an earthquake, or starved in a drought—childless.

Last but not least, many people today are able to have children but choose not to. They may remain, though, no less “successful” in every other sense of the word.

In the end, I think these exceptions, instead of weakening Dawkins’ point, strengthen it—as if each living organism could say with conviction, see, so many different pieces, not only the genes but the circumstances too, had to fall into place for me to be here. And they did.