Science

A few weeks ago, I was immersed in the splendor of Bryce Canyon. The one word that most often cropped up whenever Park Rangers described our surroundings was “unique.” We were told how “nowhere else in the world” are the “hoodoos” (the name given to the odd rock formations that are the Park’s main attraction) as abundant, as varied and as spectacular as in Bryce Canyon. I can believe it.

The origin of these hoodoos can be traced to a unique combination of “frost wedging” erosion combined with acidic rainwater acting on the limestone that primarily makes up the Canyon’s cliffs.

This started me thinking — the late-at-night-when-you-can’t-sleep sort of thinking.

What if, back in time, one of these factors had been slightly different? These Bryce Canyon hoodoos might have never been created and we would not be enjoying them today. Given that the Canyon is “unique,” this further means that there would be no other place on Earth with such hoodoos. In the end, we would likely never know that something like Bryce Canyon was a possibility.

Taking this to its next logical step, it suggests that there may well be other incredible geological possibilities that we have no idea could exist — because the “unique” conditions required for their formation have never occurred.

When you think about, why stop with geologic formations? By the same logic, there are a likely uncountable number of plant and animal species that might have appeared on Earth over the course of evolution — but never have. We have no idea what these species might be like. We do know that there have been some amazingly weird species that have existed but have since gone extinct. Potential species that have never existed at all could be even weirder.

In fact, according to some scientists, it’s actually quite lucky that we humans exist. Rather than some predictable culmination of the evolutionary process, we may well be a “unique” evolutionary accident — much like Bryce’s hoodoos.

Stephen J. Gould made exactly this sort of argument in Wonderful Life. Sure, natural selection played an important role. But, at key points in our history, there were forks-in-the-road. Natural selection was not always the deciding factor determining which direction was taken. For example, the earliest chordates (our “backboned” ancestors) appeared during the Cambrian period. At least one such chordate species survived the mass extinction of species that followed. If not, we would not be here today. However, there was no guarantee that such a species would survive. Chordates did not have some clear selective advantage at this early stage. Bad luck (a long drought in the “wrong” place at the “wrong” time) and these early chordates might have gone extinct. If so, as the argument goes, the eventual evolutionary path that led to humans would have been stopped in its tracks.

As Gould put it: “Wind the tape of life back…and let it play again. If {a chordate} does not survive in the replay, we (humans) are wiped out of future history…”

In the same way, the emergence of mammals as the major large animals on the planet might have never happened if a unique and unpredictable event (a meteor?) had not led to the extinction of dinosaurs. Without such an event, this too might have short-circuited the eventual appearance of humans.

In the end, Gould concludes that the odds that humans would ever come to exist on Earth (actually the odds that any sort of large multi-cellular organisms would ever exist) is incredibly small — despite the generally favorable-for-life conditions that existed on Earth from its very beginning.

Reflecting on all of this, I extrapolated one more step — to the possibility of life (especially “intelligent” human-like life) on other planets. Some argue that, given the presumed nearly infinite number of planets in the universe, there must be life like ours on at least a few other planets out there. Perhaps. But maybe life on Earth is “unique” — in a similar way to the hoodoos in Bryce Canyon. Maybe, despite the size of the universe, the probability of the evolution of intelligent life is so low that we are the only planet where it occurred.

Let’s go one step further. Even if there are human-like species elsewhere in the universe, what are the odds that they have iPhones? I don’t mean this facetiously. What I really mean is this:

As with humans or hoodoos, the appearance of iPhones (or any other similar technological device) is the result of a lengthy cascade of necessary preceding events. Before Apple could invent the iPhone, there needed to be Mac OS X, cell towers and more primitive smartphones. There needed to be an Internet and a World Wide Web. And that’s just the recent stuff. Going back further, there needed to be computers in general, whose existence required the invention of integrated circuits which, in turn, were derived from transistors that were the descendants of vacuum tubes. All of these technologies couldn’t exist without modern manufacturing techniques, which are in turn dependent on electricity. And back and back we go…to the prehistoric invention of the first tool by a hominid species.

In some sense, all the natural materials needed to build an iPhone have been present on Earth for millions, perhaps billions, of years. But it required this lengthy train of events before the materials could be assembled into Apple’s superstar device. Were these events inevitable — at least once hominids appeared on Earth and the ball really began rolling? If so, we should expect an iPhone, or something quite similar, to exist everywhere else in the universe where human-like creatures might have evolved.

Or, as suggested as possible via Gould’s hypothesis, might the iPhone be the result of a series of (sometimes lucky) events that are unlikely to be duplicated elsewhere — even on other planets with species otherwise similar to our own (assuming such planets exist)? If so, we might be the only species in the universe with iPhones — or anything close to it. We could be the only species who can, as E.T. put it, “phone home.”

Or maybe there’s an alien Steve Jobs somewhere on a distant planet, just now getting ready to reveal his company’s iPhone at a Special Event. Hold on; I’m going to check my email. Maybe I got an invitation.