is the easiest way to share online.
Learn more »
Life: is it inevitable or just a fluke? By Nick Lane -
July 7, 2012
"The optimistic assumption of the Drake equation was that on planets where life emerged, 1 per cent gave rise to intelligent life. But if I’m right, complex life is not at all inevitable. It arose here just once in four billion years thanks to a rare, random event. There’s every reason to think that a similar freak accident would be needed anywhere else in the universe too. Nothing else could break through the energetic barrier to complexity. This line of reasoning suggests that while Earth-like planets may teem with life, very few ever give rise to complex cells. That means there are very few opportunities for plants and animals to evolve, let alone intelligent life. So even if we discover that simple cells evolved on Mars, too, it won’t tell us much about how common animal life is elsewhere in the universe. All this might help to explain why we’ve never found any sign of aliens. Of course, some of the other explanations that have been proposed, such as life on other planets usually being wiped out by catastrophic events such as gamma-ray bursts long before smart aliens get a chance evolve, could well be true too. If so, there may be very few other intelligent aliens in the galaxy. Then, again, perhaps some just happen to live in our neighbourhood. If we do ever meet them, there’s one thing I would bet on: they will have mitochondria too." -
A really excellent description of why simple life is probable and complex life is so improbable, it's all about energy. -
©2013 FriendFeed -
Tools & Widgets