Accident or destiny?

Accident or destiny?

A fossilized trilobite preserved in Burgess Shale • Photo by Smith609 (CC BY 2.5)

Originally published 26 June 2005

For the first four bil­lion years of Earth his­to­ry, life was ame­bic and micro­scop­ic. Then, about 600 mil­lion years ago, with sur­pris­ing swift­ness, a myr­i­ad of mul­ti­cel­lu­lar organ­isms appear in the fos­sil record, in what has been called the Cam­bri­an Explosion.

This new diver­si­ty of life is beau­ti­ful­ly pre­served in fine-grained mud­stones of West­ern Cana­da called the Burgess Shale. Here are crea­tures with ances­tral sim­i­lar­i­ties to present ani­mals — jel­ly­fish and sponges, for exam­ple — but also a teem­ing menagerie of weird ani­mals whose lin­eages were des­tined for extinction.

The late great evo­lu­tion­ist Stephen Jay Gould looked at the Burgess Shale and saw a record of con­tin­gency and chance. In a book called Won­der­ful Life: The Burgess Shale and the Nature of His­to­ry (1989), he argued that evo­lu­tion is a crap shoot, not so much the sur­vival of the fittest as the sur­vival of the luckiest.

Play the tape of his­to­ry again, said Gould, and the out­come would almost cer­tain­ly be dif­fer­ent. You and I might not be here.

Simon Con­way Mor­ris, an expert on the Burgess Shale, looks at the same fos­sils and draws a dif­fer­ent con­clu­sion. In The Cru­cible of Cre­ation: The Burgess Shale and the Rise of Ani­mals (1998), he attempts to show that envi­ron­men­tal pres­sures dri­ve evo­lu­tion in a pre­dictable direction.

Yes, there is a cer­tain dici­ness, says Mor­ris, but when one crea­ture suc­cumbs to caprice — an aster­oid impact, say, or cli­mate change — anoth­er will evolve to fill the vacat­ed niche. Con­ver­gence — the ten­den­cy of remote­ly relat­ed lin­eages to evolve along sim­i­lar lines — is a pow­er­ful a force in evo­lu­tion, he says, and con­ver­gence leads inevitably to some­thing very like us.

Mor­ris upped the ante and gave the sto­ry a reli­gious twist with his more recent book, Life’s Solu­tion: Inevitable Humans in a Lone­ly Uni­verse (2003). Bil­lions of years of evo­lu­tion were reach­ing in our direc­tion, he sug­gests: “The evo­lu­tion­ary routes are many, but the des­ti­na­tions are limited.”

Con­tin­gency vs. inevitabil­i­ty. The roll of the dice vs. some­thing very like a divine plan. Two views of his­to­ry by two bril­liant sci­en­tists draw­ing their con­clu­sions from the same sci­en­tif­ic data. One view makes human life a fluke, the oth­er places human­i­ty at the pin­na­cle of a grand unfolding.

No doubt the truth lies some­where in between. Evo­lu­tion is not, as cre­ation­ists mock­ing­ly sug­gest, a thou­sand mon­keys bang­ing away at type­writ­ers and com­ing up with the works of Shake­speare. Nor is it the famil­iar sequence of crea­tures crawl­ing onto the shore, then turn­ing step by step into mod­ern humans — an image Gould loved to poke fun at.

The pow­er — and beau­ty — of the neo-Dar­win­ian syn­the­sis is the way it incor­po­rates both chance and law. We may not be the inevitable apple of the Cre­ator’s eye, but intel­li­gent crea­tures such as our­selves may indeed have been a like­ly out­come of organ­ic evo­lu­tion. After all, big brains, self-aware­ness, tool­mak­ing and sci­ence have enor­mous sur­vival val­ue in a chancy universe.

All of this has rel­e­vance to how we respond to the present envi­ron­men­tal cri­sis. If his­to­ry is a crap shoot, there’s not much any one of us can do to nudge it one way or the oth­er. And if his­to­ry is pre­de­ter­mined, we might as well all set back and wait for the inevitable unfold­ing, what­ev­er it is.

But if the truth falls some­where between “any­thing goes” and the apoth­e­o­sis of humankind — and that is where lies the nexus of sci­ence and spir­it — then our actions have consequences.

To the extent that his­to­ry depends on the roll of the dice, we can be smart enough to load the dice to the plan­et’s advan­tage. And if, as Mor­ris implies, there is a direc­tion to his­to­ry which places humans in a spe­cial redemp­tive role, we can assume that role with gus­to and act it to the hilt.

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