London, Nov 5: Humans could have more in common with our extra-terrestrial neighbours, than initially thought, new research suggests.
The findings, led by scientists from the University of Oxford, revealed that aliens are potentially shaped by the same processes and mechanisms that shaped humans, such as natural selection.
The new theory supports the argument that foreign life forms undergo natural selection, and are like us, evolving to be fitter and stronger over time.
"In the study, we offer an alternative approach, which is to use evolutionary theory to make predictions that are independent of Earth's details. This is a useful approach, because theoretical predictions will apply to aliens that are silicon based, do not have DNA, and breathe nitrogen, for example," said Sam Levin, a researcher at the varsity.
Using this idea of alien natural selection as a framework, the team addressed extra-terrestrial evolution, and how complexity will arise in space.
The study, published in the International Journal of Astrobiology, also makes specific predictions about the biological make-up of complex aliens, and offers a degree of insight as to what they might look like.
"We still can't say whether aliens will walk on two legs or have big green eyes. But we believe evolutionary theory offers a unique additional tool for trying to understand what aliens will be like, and we have shown some examples of the kinds of strong predictions we can make with it," Levin added.
"There are potentially hundreds of thousands of habitable planets in our galaxy alone. We can't say whether or not we're alone on Earth, but we have taken a small step forward in answering, if we're not alone, what our neighbours are like," he added.