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As a biologist, it's pretty cool, although not quite as cool because it's the same life. Different life, evolved on different planets, would be cooler. It wou
by mnemonicsloth 7y ago
As a biologist, it's pretty cool, although not quite as cool because it's the same life. Different life, evolved on different planets, would be cooler. It would use some of the same tools, like phosphates as signaling/energy molecules, because nothing else can do the job. But alien life could use different amino acids from the ones we use, or something different from amino acids instead. They would probably be linear polymers of related monomers though. The same goes for DNA: different base units probably, but still a linear polymer, and very possibly a helix (lots of things are helices).
But the problem with all these instances of life is that all but n of them have to get snuffed out before they've developed much further than we are, and so far as we know n has to be either 1 or 0.
- aaronblohowiak 7y agoDon’t pressures and temperatures impact which chemical classes can do which job?
- mnemonicsloth 7y agoIt depends on how far out you want to get. It's possible life could exist on neutron stars, or in stellar photospheres, or in the atmospheres of gas giants. And life might not be obvious. Life as we know it is not an obvious prediction given carbon, hydrogen, oxygen and nitrogen as a starting point. So maybe it turns out that certain combinations of minerals do something interesting when you immerse them in an ocean of liquid chlorine. We wouldn't know. But so far as we know for sure, life has to start with liquid water, which narrows the range of admissible temperatures to 0-100 C and pressures around 1 atmosphere. Hyperthermophile bacteria can live in boiling water (up to 120C). We use some of their enzymes to do genetic engineering on normal cells. The temperature change isn't enough stop the hyperthermophile proteins from functioning (and they're pretty sensitive). Likewise there are psychrotolerant (cold-dwelling) cells that can live near 0C, using mostly normal proteins. So I think life as we know it is locked into one regime of "normal" chemical behavior.
- nickthemagicman 7y agoAlso as a biologist,finding life on other planets..no matter what the form...would be mind blowing as fuck to me. Sorry you're so jaded.