Researchers from the University of Oxford have suggested that extraterrestrial life forms may resemble humans more than the monster-like beings often depicted in science fiction. In a new study, they argue that evolutionary theory can be used to predict alien behaviour and appearance, indicating that natural selection shapes life across the universe in similar ways.
The study, led by Sam Levin, proposes that aliens undergo natural selection and major evolutionary transitions, just as species on Earth have. These transitions occur when separate organisms evolve into a higher-level entity, such as when cells form multicellular organisms. The researchers believe that extreme conditions are required for such transitions, and the same may apply to alien life.
While the team cannot specify details like bipedalism or eye colour, they assert that complexity arises through a hierarchy of cooperating entities. Levin stated: 'By predicting that aliens have undergone major transitions... we can say that there is a level of predictability to evolution that would cause them to look like us.'
The study offers an alternative approach to astrobiology, using evolutionary theory independent of Earth's specific chemistry or biology. Levin noted: 'Theoretical predictions will apply to aliens that are silicon based, do not have DNA, and breathe nitrogen, for example.'
