It is highly likely that human-like aliens have evolved on other planets, one of Britain's leading evolutionary biologists has claimed.

Simon Conway Morris builds on the principal of convergent evolution – that different species will independently evolve similar features – and argues that it could happen on any Earth-like planet.

"I would argue that in any habitable zone that doesn't boil or freeze, intelligent life is going to emerge," says Conway Morris in his new book called The Runes of Evolution.

The principle of convergence suggests that evolution is not random, but a predictable process that operates according to a "fairly rigid" set of rules, says Phys.org.

Conway Morris, who is a Cambridge fellow, argues that large brains, intelligence and tool-making skills are all convergent, so what applies on earth will apply across the Milky Way and beyond if the conditions are right.

"One can say with reasonable confidence that the likelihood of something analogous to a human evolving is really pretty high," says the English scientist. "Given the number of potential planets that we now have good reason to think exist, even if the dice only come up the right way every one in 100 throws, that still leads to a very large number of intelligences scattered around, that are likely to be similar to us."

So what about the famous paradox – if intelligent life exists, why hasn't it made contact? "The almost-certainty of ET being out there means that something does not add up, and badly," said Conway Morris. "We should not be alone, but all the evidence suggests we are."

The scientist told The Independent that he went "off-piste for a bit of fun" in the last chapter of his book when dealing with this problem.

"Maybe [aliens] are hiding, the Arthur C Clarke idea, or as Stephen Baxter mischievously suggested we live in a virtual world," he said.

"I don’t honestly know. My suspicion is we have only begun to scratch at the surface of reality."