Why Evolution Will Work Against Interstellar Civilizations
Over the horizon, long term planning is not the strong suit of great apes like us. Homo sapiens are highly socialized animals prone to cooperate when necessary. But we are just as prone to strike up an argument with the next clan over, be they on the ancient savannas of East Africa, or the neighbors next door.
But long-term planning is what any high-tech intelligent civilization will need if they are to overcome the physics of our own cosmos, as laid out by Einstein more than a century ago in his theory of relativity.
Any path across interstellar distances – generational starships, hibernation, self-replicating probes or (if ever physically possible) speculative spacetime engineering – is as much a civilization-scale coordination and commitment problem as a physics or engineering problem, Kathleen Bryson, an evolutionary anthropologist and postdoctoral researcher at the U.K.’s De Montfort University in Leicester, tells me in Oxford.
But Bryson also thinks that our potential cosmic brethren, be they friends or foes, will be hamstrung by some of the same problems that plague our own human civilization.
That is, a lack of focus in overcoming great societal challenges such as climate change, sustainable agriculture and yes, even long-duration human space flight.
The crux of it all is an evolutionary concept known as convergence.
When environments impose similar constraints, evolution tends to find similar solutions, Bryson argues in a recent talk at the European Astrobiology Institute’s BEACON25 conference in Reykjavik, Iceland. Convergent evolution refers to the independent emergence of similar traits in unrelated lineages – like flight in bats and birds, she notes in her talk. It’s not that flippers or wings are inevitable, it’s that they’re statistically likely under the right evolutionary pressures, Bryson points out in her presentation.
While social traits appear to be convergent among different species here on Earth, there’s also no reason to think that something similar would not happen elsewhere in our great cosmic beyond, Bryson argues in her Reykjavik talk.
Basic Functions
Eyes, heads, tails, and sexual organs are convergent. Even some forms of excretory systems are convergent. But Bryson says that behavior is often convergent as well.
Darwin Still Wins
These same Darwinian evolutionary principles would likely also hold up on exoplanets, says Bryson. We would not necessarily expect extraterrestrials to have the same body shapes, but we would expect similar convergent behavior, she says.
Bryson says that hormones also play a role in each species’ long-term destiny.
Some of the hormones that make us behave more cooperatively, like oxytocin, also cause xenophobia, says Bryson. Thus, if extraterrestrials are at the level of space travel, they would likely have some of the same behavior as we humans, including xenophobia, she says.
Here on Earth, one could argue that xenophobia can jumpstart the quest for new technology, as during the Cold War. But lately, there seems to be little or no constituency for long-term space missions. The career span of a given physicist or aerospace engineer is maybe 50 years at most. So, to facilitate long-term thinking about space exploration and interstellar travel, there almost must be a cathedral-building mentality.
That is, a need to look beyond a single generation to address civilization-scale projects, as happened during the history of the building of the great cathedrals of Europe. Cases in point, England’s Winchester Cathedral took nearly 500 years to construct, while Germany’s Cologne Cathedral took over six centuries to complete.
In the last century, we put astronauts on the Moon within 100 years after the first powered, heavier than air human flight. The Moon walks were a remarkable achievement, but they were followed by decades of lassitude and indecision when it came to pushing the envelope of human space flight.
As For E.T.?
Evolution tends to reward creatures who look after the near future not those who run thousand-year plans, says Bryson. On any world, if life is risky or resources swing wildly, you grab what’s in front of you, she says. Only in safer, longer-lived setups do horizons stretch a bit (and even then, the short-term pull never fully disappears), says Bryson.
A Lack Of Commitment
Call me cynical, but if E.T. is anything like us, they will not do the hard work of breakthrough propulsion research that will be necessary to voyage to the stars.
I think that they would also have problems with long-term investment, because of convergent behavior like our own, says Bryson.
The Bottom Line?
Getting across interstellar distances is as much about civilization-level commitment as it is about speculative warp drives, says Bryson. My bet is that even for highly social, intelligent aliens, true interstellar pushes will be rare, fragile and come in bursts, she says.