Archive for November 25, 2014

What’s Life?

Some people say “Life’s a bitch.”  Some say “Life’s a beach!”  But if you ask an evolutionist, someone who devotes his or her career to the question “What’s Life?” the answer may stun you.  Especially if you’re curious about attachments and Ebola.

People who think about evolution for a living don’t think like us.  They measure time in billions of years.  They talk about genetic and cosmic events in the same sentence.   They observe nature with the eye of Audubon and then describe features of a species as the results of natural selection through the mathematics of mutation probabilities.

We need a translator.  Richard Dawkins may be to the science of evolution what Stephen Hawking is to the science of physics: a champion voice for the lay audience.  Dawkins’ book (2009) The Greatest Show on Earth presents a compelling argument for understanding life in terms of the talent for attachments at every level of organization of matter—from the tertiary structure of our enzymes to the chemical bonds forming DNA to our attachments with each other and our gods.  Life is all about attachments.

Consider the enzymes, the millions of proteins that catalyze the reactions that make us tick.  The sequence of amino acids in a protein determines how that chain folds in on itself, bonding one part of the chain to another to form a stable “tertiary structure,” like the knot in a rope, that defines which sites on the protein are available for interacting with other molecules.   That’s one kind of bonding essential for life.

If you throw enough carbohydrates and purines into a soup bowl called Earth and wait long enough, perhaps one or two billion years, some of these molecules may eventually organize themselves into single and double helices.  Some of these helices will replicate themselves by unzipping along an internal seam and bonding with their complementary counterparts at every tooth of the zipper to create a new copy—the magic of DNA.  A molecule that copies itself will thrive.  A molecule that copies itself and organizes amino acids into chains of proteins will thrive even better because it builds blocks for the house that protects it: DNA wrapped in a membrane, or the cell.

Molecules that copy themselves while programming their cells to divide without dying do better than the less well connected molecules.  This process of dividing the intracellular goods and multiplying eventually created viruses and bacteria.  The DNA recipe that makes them tick is the same recipe that makes our cells tick, a recipe for a sequence of reactions that leads to cell survival and replication.    You think the Human Genome Project was a feat?  Imagine mapping the sequence of reactions that turn a human embryo from two cells into a baby that wails!

Listen to Dawkins in the most striking chapter of the book, Chapter 8, called “You Did it Yourself in Nine Months,” his review of how a fertilized egg divides and organizes itself into a baby (p 247):

     “There is no overall plan of development, no blueprint, no     architect’s plan, no architect.  The development of the embryo, and  ultimately the adult, is achieved by local rules implemented by cells, interacting with cells, on a local basis.  What goes on inside cells, similarly, is governed by local rules that apply to molecules, especially protein molecules, within the cells and in the cell membranes, interacting with such molecules.  Again the rules are all local, local, local.”

The stunning lesson to take from this book is that the growth of an egg is inherent in the properties of the molecules contained in the egg and its surroundings:  all by “local rules.”  This process of embryo development has been mapped out for each one the 558 cells that form the nematode worm larva; similar processes guide the development of the human embryo.    Genes coordinate the events by being turned on and off in a sequence that is the lone survivor of all sequences, after being tested in trillions of trials over billions of years in countless species.  The failures died away.  Nature throws out the garbage.  We only know the successful survivors.

So, according to evolutionists like Dawkins, you and I are accidents of nature.  And we’re also the accumulated “wisdom” of all the accidents that have perpetuated the re-creation of life.  It’s hard to think the way Dawkins does. No wonder many people prefer to believe God created this world ten thousand years ago, in a six-day week.  It’s harder to believe that joining the volleyball team, cuddling your puppy, swooning for Michael Jackson, and praying to Allah are just more complex forms of what life is at every level:  the talent for making attachments that help us survive.

Life is just those sets of bonds that can both replicate themselves and survive the contest with other forms of life.  All else has vanished to extinction, which is where we would like the Ebola virus to go.  This Ebola epidemic shows us evolution in action.  Some RNA wrapped in a protein sheath, likely a mutation from an earlier virus, is having a blast replicating in the bodies of a few thousand West Africans.  Ebola’s survival will depend in part on how it competes against the strength of social attachments formed in our human species, such as the United Nations Mission for Ebola Emergency Response .  If we humans can’t organize ourselves to constrain Ebola’s replication, our species could lose that contest and Ebola could thrive at our expense.  That’s life.

But we should take heart from Jeremy Rifkin, who has spelled out in The Empathic Civilization (2010) how our species has evolved toward increasingly empathic behaviors, such as managing a distant epidemic.  I find it heartening to understand that this progress toward a more empathic, compassionate world community is neither the luck of the draw nor the triumph of good over evil.  It’s the nature of life.  At every level of organization of matter, including our social networks, we make bonds that favor our survival.  Failure to do so is punished by death and extinction.  That’s life.