Is anybody out there? What Darwin can teach us about how aliens might look | Samuel Levin
Aliens could be everywhere. There are at least 100bn planets in our galaxy alone, and at least 20% of them could be habitable. Even if a tiny fraction of those planets - less than 1% of 1% - evolved life, there would still be tens of thousands of planets with aliens in our vicinity. But if we want to figure out where to start looking for these neighbours, we need to understand what they might be like and where they might thrive.
Ultimately, we want to understand as much as possible about an extraterrestrial species before we encounter it. Yet making predictions about aliens is hard because we have only one example - life on Earth - to extrapolate from. Just because eyes and limbs have evolved many times on Earth doesn't mean they will appear even once elsewhere. Just because we are made of carbon and coded by DNA doesn't mean aliens will be - they could be silicon based and coded by "XNA".
Continue reading...