4 ms·

In any case, score one for science. Science, 15. Religion, 4. GOOO hometeam!

gscott 18y ago
I am wondering why evolution happens here and not elsewhere. Every planet in our solar system has been hit by comets, has a cycle of night and day, etc. We should be seeing evolution on the planets near us. For example in the Russian nuclear reactor that failed there is a bacteria that has adapted to feeding off of radiation. So life can happen in the most extreme circumstances. Just because other planets of extreme circumstances doesn't exclude them from evolution.
- cstejerean 18y ago
  I assume that first life has to develop, and then it has a chance to evolve. So it's possible some places lack the necessary components for life to develop. But it's certainly possible for primitive life forms to exist in other parts of our solar system.
  - natch 18y ago
    Life is tricky to define, but the most likely scenario is life does not develop first - it develops only after a process of evolution of replicating stuff that would not be considered alive by most definitions. Eventually, after billions of years with trillions of petri dishes worth of different little evolution experiments all happening in parallel on each of billions of planets, some of them gain replication mechanisms that are complex enough that they could be considered alive. Evolution leads up to this point, and continues after it.
- natch 18y ago
  Who said evolution happens only here and not elsewhere?
  - gscott 18y ago
    I am interested in seeing some evolution on other planets. We have a number of planets nearby that are as old as our own. Evolution should be at the same pace on those planets. Life comes in many forms (bacteria on radiation as I mentioned before) so we should see some sort of life on other planets even though it is not life i.e. a dog, cat or plant that we are most familiar with. Preferably something that moves or at least recreates itself (spawns). Evolution is a fact, there is natural selection, certain offshoots of species die out (fail to adapt), etc. But the really curious thing is that we can't point out and say hey yeah evolution is happening over there too.
    - mark-t 18y ago
      Just because two planets have been around for the same amount of time in similar conditions doesn't mean they should both exhibit life. The emergence of self-replicating molecules at any given time may be extraordinarily unlikely, such that the expected amount of time for it to happen is on the order of trillions of years. However, when you've got several planets in the same circumstances, one of them will likely succeed much sooner than the others. Here's a more concrete example. Consider the odds of rolling a 528 on a 1000 sided die, and you have 5 people rolling such a die. The expected number of rolls for any individual to get a 528 is 1/1000 + 2 * 999/1000^2 + 3 * 999^2/1000^3 + ... = 1000. However, the probability that at least one person has rolled a 528 passes 50% after n rolls, where (999/1000)^(5n) = .5, or n = log(.5)/(5log(.999)) = 139. In other words, you expect to have rolled a 528 after 1000 rolls on average, but you expect somebody to have rolled one after 139.
      - LPTS 18y ago
        I don't see why we should consider the evolution of DNA to be unlikely. We have increadible statistical evidence it isn't. Chance you evolved in a universe you observe: 100% Chance you evolved in a universe you dont: 0% Given: I exist. Therefore, from clear first principles, I should judge as 100% the chance of DNA evolving. I dont get how any conscious being could even concieve that percentage as less then 100.
- eru 18y ago
  Any sources for the radiation feeding bacteria?

I am wondering why evolution happens here and not elsewhere. Every planet in our solar system has been hit by comets, has a cycle of night and day, etc. We should be seeing evolution on the planets near us. For example in the Russian nuclear reactor that failed there is a bacteria that has adapted to feeding off of radiation. So life can happen in the most extreme circumstances. Just because other planets of extreme circumstances doesn't exclude them from evolution.

cstejerean 18y ago
I assume that first life has to develop, and then it has a chance to evolve. So it's possible some places lack the necessary components for life to develop. But it's certainly possible for primitive life forms to exist in other parts of our solar system.
- natch 18y ago
  Life is tricky to define, but the most likely scenario is life does not develop first - it develops only after a process of evolution of replicating stuff that would not be considered alive by most definitions. Eventually, after billions of years with trillions of petri dishes worth of different little evolution experiments all happening in parallel on each of billions of planets, some of them gain replication mechanisms that are complex enough that they could be considered alive. Evolution leads up to this point, and continues after it.
natch 18y ago
Who said evolution happens only here and not elsewhere?
- gscott 18y ago
  I am interested in seeing some evolution on other planets. We have a number of planets nearby that are as old as our own. Evolution should be at the same pace on those planets. Life comes in many forms (bacteria on radiation as I mentioned before) so we should see some sort of life on other planets even though it is not life i.e. a dog, cat or plant that we are most familiar with. Preferably something that moves or at least recreates itself (spawns). Evolution is a fact, there is natural selection, certain offshoots of species die out (fail to adapt), etc. But the really curious thing is that we can't point out and say hey yeah evolution is happening over there too.
  - mark-t 18y ago
    Just because two planets have been around for the same amount of time in similar conditions doesn't mean they should both exhibit life. The emergence of self-replicating molecules at any given time may be extraordinarily unlikely, such that the expected amount of time for it to happen is on the order of trillions of years. However, when you've got several planets in the same circumstances, one of them will likely succeed much sooner than the others. Here's a more concrete example. Consider the odds of rolling a 528 on a 1000 sided die, and you have 5 people rolling such a die. The expected number of rolls for any individual to get a 528 is 1/1000 + 2 * 999/1000^2 + 3 * 999^2/1000^3 + ... = 1000. However, the probability that at least one person has rolled a 528 passes 50% after n rolls, where (999/1000)^(5n) = .5, or n = log(.5)/(5log(.999)) = 139. In other words, you expect to have rolled a 528 after 1000 rolls on average, but you expect somebody to have rolled one after 139.
    - LPTS 18y ago
      I don't see why we should consider the evolution of DNA to be unlikely. We have increadible statistical evidence it isn't. Chance you evolved in a universe you observe: 100% Chance you evolved in a universe you dont: 0% Given: I exist. Therefore, from clear first principles, I should judge as 100% the chance of DNA evolving. I dont get how any conscious being could even concieve that percentage as less then 100.
eru 18y ago
Any sources for the radiation feeding bacteria?