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Could humans be the dominant species in the Universe, and we just do not know yet?

Could humans be the dominant species in the Universe, and we just do not know

By Paul Parsons

Could it be that our species is the major indigenous race in the Universe - that Homo sapiens, or something close to it, has evolved independently in many other worlds?

The late evolutionary biologist Stephen J Gould called this idea absurd. He argued that if you redirect evolution here on Earth, then the probability of "retrieving" humans a second time is extremely small.

His reasoning was that evolution is driven by random sets of genetic mutations, modulated by random environmental effects, such as mass extinctions, and that it would be extremely rare for the same set of effects to occur twice.

But it is a view that is not universally held. One school of thought, called 'convergent evolution', says that random effects are ultimately average, so convergent evolution will tend to produce similar organisms in any given environment. For example, pilots have evolved independently on Earth at least four times - in birds, bats, insects and pterosaurs. The eyes may have evolved up to 40 times.

One proponent of this view is Prof. Simon Conway Morris, of Cambridge University. " Convergence is one of the best arguments for Darwinian adaptation, but its ubiquity has not been appreciated," he says.

"One can say with reasonable belief that the probability that something analogous to human development is really very high. And given the number of possible planets, we have good reason to think they exist. ”