I was having a conversation with my mom and sister Tuesday, and we were speculating about life on other planets. Jane pointed out that if you hadn’t seen life in the water, you wouldn’t know it existed. Think about this for a minute, imagine you’re a scientist in a fairly arid area, you have tap water but no bodies of water to study. You study life, you know about animals and humans, you know about lungs and how they work. You’ve seen a mouse fall into a washbasin and drown, you know animals cannot extract the oxygen they need from water, you’ve tried to breathe under water and came up coughing and sputtering. Even a worm will die in the water. You have heard that there are great bodies of water far away, but you have no transportation. You assume that these bodies of water must be lifeless, for nothing you have ever seen or heard of can live in the water. In fact, you know from research, no life can survive in water. Then a fellow scientist comes by in his high speed hovercraft, whisks you off to an ocean, where you see fish, whales, eels, starfish, urchins, and all matter of sea life. You quickly learn the difference between those that can hold their breath for extended periods of time (much longer than you could have imagined) and those that breathe the water through gills. This is a different form of life than you’ve ever seen, yet much more similar than you imagined possible. They breathe through slits, yet they have bones and muscles like everything you know, they can be touched, they have sensation, reaction, this is life like you know it, living under water. What you knew for a fact is now incredibly wrong.
OK, now imagine you are a scientist on a tiny planet called earth. You have heard of Jupiter, studied it, and you know how life works. Jupiter is too far away for you to visit, though, so your conclusions are made from a distance. You know no life can exist on Jupiter. It is a planet of gas storms, and nothing could breathe the hydrogen, there is no solid surface to stand on, it cannot support life as we know it. Right?
The reason we are lucky enough to live on a planet that can support us doesn’t actually have to do with luck. We evolved to survive on our given planet. We evolved to breathe this air and eat these plants because they are what is here. Could this not have happened on other planets?
As for intelligent life, I’m an optimist. I don’t think we need to look for it on other planets, I think if we keep searching, someday we may find it here.