--- In [email protected], "PaliGap" <compost...@...> wrote: > > > > --- In [email protected], "hugheshugo" <fintlewoodlewix@> wrote: > > > > --- In [email protected], "PaliGap" <compost1uk@> wrote: > > > > > > --- In [email protected], "Hugo" > > > <fintlewoodlewix@> wrote: > > > > > > > Amongst all the staggering coincidences and apparently > > > > rare requirements that common organic molecules have to > > > > go through in order to become complex life forms I forgot to > > > > mention that the trigger (for their always is one in leaps > > > > of evolution) for life to go from the happy bacterial state > > > > it was in for 3 billion years into it's post-cambrian > > > > cornucopia is the fact that the Earth was frozen solid for > > > > millions of years thus the only survivors were the bacteria > > > > that mutated into the cell that make up *all* living things > > > > today. > > > > > > > > This isn't creationism, it's hard empirical science and is > > > > easily checkable. > > > > > > I don't get this Hugo. > > > > > > Are you saying that "snowball earth" was a pre-requisite for > > > our planet's rich life-status? > > > > It might very well have been yes. On one side of the freeze > > you have just bacteria no the other you have everything we know > > today. > > > > And that this is hard science? > > > I did a quick-and-dirty wiki check and got the impression Life > > > arose *despite* the conjectured snowball Earth, not > > > *because* of it. > > > > Can't believe everything you read on the internet I'm afraid. > > > > I'm talking about the change from simple single-celled stuff > > before a major cataclysm to a stronger type of cell (that ALL > > life now shares) the improvements in cell structure may well > > have been forced on us by environmental pressure. Bit too > > much of a coincidence otherwise. > > > > > The fact that one event precedes another event does not in > > > itself make it a "trigger" does it? Or have I misunderstood > > > you? > > > > Probably. In this case you'd have to prove that the freeze > > *wasn't* the trigger and come up with some other explanation > > for the arrival of complex life when, for 3 billion years, > > before a sudden massive change in climate there wasn't any. > > And that's the "hard empirical science"? No mechanism (it seems) > and just a lack of other explanations? ;-)
No mechanism, oh please! > Actually, when you say this: "Bit too much of a coincidence > otherwise" - doesn't that really count against the more > general point you are trying to make? Viz. *Our* Life may > be just some highly improbable coincidence. After > all, if there is an *explanation* for turbo-boosted Cambrian > explosions, and the explanation is just this: That the biology > needs serious stress testing to fire it up... Then what you > need to show is that such stressing is rare and unusual around > the galaxy. Which is...unlikely? *Probably* not! if the only > explanation is a Gallic shrug and "coincidence!", then yes, > maybe so. > > (By the way - who is it that is asserting this theory viz. > "a snowball planet may be a necessary condition for complex > life"? It's not a HugoFintlewoodLewix *special* is it?) Oh dear. The theory isn't that a world needs to go through a deep freeze in order for complex life to evolve. The thread is a response to the idea that complex, indeed conscious life is a given wherever organic molecules arise. I am just pointing out that there was a long path to the complexity seen on earth that may not have "just" happened as though it was inevitable, but the very fact that it took so long is a bit of a giveaway when the CE happened right after a serious bit of environmental pressure on the bacteria swimming around at the time. On Earth, the snowball theory might be absolutely essential to explain the cambrian explosion or it may not, if it isn't why did life wait so long before diversifying so much? *That* would be the coincidence. Or it may have come about because of a different environmental pressure. Seems rather likely though that because it took 3 billion years *then* an environmental catastrophe (as far as bacteria are concerned) before life got really interesting seems like a bit of a give- away. If complex life would have happened anyway, why not straight away? You have to look at it in the context of why species change anyway and that is because the world changes and they have to adapt. Could be predators, environmental change. Species drift genetically anyway but selection pressure makes it happen fast. But without the joining of the two ancient bacteria that give us the modern cell everything is based on we wouldn't be here and that only happened after 3 billion years, question is: would it have happened without sufficient pressure from the environment? Would we still all be happily swimming in our primordial stew without the big snowball? Seems likely, 3 billion years is an awful long time.... Do you ever actually think about things like this, there is big (and growing) belief that complex life is an inevitable consequence of there being organic molecules all over the universe. I say it isn't inevitable but more likely to be a result of so many unlikely-to-be-repeated coincidences it may well have happened only once. Until some aliens show up or we can examine the atmospheres of some of those recently discovered planets we aint gonna know for sure.
