So
if the extraterrestrials are out there, are they small and cute like
E.T.? Or are they remorseless monsters like the aliens in Alien? Do they
have thin bodies and big eyes like just about any other
extra-terrestrial in just about any other movie?
Or, maybe, do they look like us?
Prof. Simon Conway Morris is a paleontologist at Cambridge University in England. His new book, The Runes of Evolution,
argues that the enormous number of Earth-like worlds now being
discovered could – and should – give rise to Earth-like creatures.
“Over a number of years I’ve been arguing that evolutionary
convergence – the ability for similar, sometimes almost identical
structures to evolve independently – is something which is not merely
widespread, but is basically ubiquitous,” he says in an interview with
Yahoo Canada.
“The classic example being something like the eye of the squid
and octopus, which developed separately from the eye of the human. It’s
very, very common, and I think its importance is being underestimated.”
Since the launch of the Kepler space telescope in 2009, rocky
planets more-or-less the size of Earth are being discovered by the
thousand. They’re too far away to know for certain if they can support
life, but the sheer size of their ever-growing numbers is growing
evidence that we are possibly not alone.
“Something like a human evolving is actually much more likely than had hitherto been thought,” Conway Morris said.
“Habitable zones will vary, but the estimate is that there’ll
be a very large number of planets which will be in positions closely
analogous to the Earth. And if indeed live evolves on them, my view
would be that the likelihood of something like a human – with
intelligence and technology and language ultimately – is high on the
stakes of probability.”
Which, again, raises the timeless question: Where are they?
“There are many star systems that are eight or nine-billion
years old. And then here we come rather recently. The problem then is,
if you make some fairly unexceptional assumptions about the way in which
migration would occur across a galaxy, it doesn’t actually take that
long.”
We should have company, in other words. Company which, if we met them face-to-face, might not look all that different from us.
“Something just doesn’t add up here, big time,” he argued.
“That’s my driving interest in this area. And it may be something
mundane, like the origin of life just is fantastically unlikely, a
fluke. Or it may be that intelligent civilizations destroy themselves,
and just cannot get a stable society.”
These newly-discovered worlds will be home to a wide range of
environments – too hot, too cold, too corrosive, too much (or not
enough) gravity. But Conway Morris argues there is already an enormous
range of temperatures and pressures on Earth, and life seems to find a
way in almost all of them.
“The biospheres, in their totality, would be the most amazing zoo,” he said.
And many of that zoo’s creatures, he unshakeably believes, would be familiar to us.
