Asked by: Claire Price, Merthyr Tydfil
Evolve by natural selection? Definitely not. Genes to help deal with radiation and low gravity aren’t impossible, and eventually humans would probably evolve these adaptations. But evolution won’t help us with the Martian atmosphere. Natural selection needs an environment that kills the weak but lets the strong survive. Mars has almost no atmosphere and none of it is oxygen, which means that it is 100 per cent fatal to everyone. You’ll have three minutes to evolve to breathe CO2 before you suffocate, and after that you won’t make any further contribution to the gene pool. Even if you kept Mars colonists inside a pressurised dome and ever so gradually reduced the pressure and oxygen concentration over hundreds of thousands of years, it wouldn’t help us to evolve.
Natural selection might evolve better and better ways to manage on what little oxygen there was, but it is never going to give us cells that don’t need oxygen at all. We burned that evolutionary bridge two billion years ago. We will adapt to life on Mars by using technology, and it would actually be easier and faster to add oxygen to the Martian atmosphere, than for us to evolve to live without it!
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.