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I didn't see you'd posted it.
I don't really know what you mean when you say "best." A decrease in entropy is something we've used to look for life on Mars and elsewhere, because it provides a pretty easy definition of life that doesn't necessarily limit us to looking for life as we know it.
So.. all life is good at doing it, but which would be the best, I have no idea off the top of my head, and no idea how we'd go about even finding that out. Or why.
"There's no better public education than teaching kids that they should have been born to a parent who could afford their cancer treatments." - @LOLGOP
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Great breakdown/chart on that here: http://evolution.berkeley.edu/evosit...bBeetles.shtml
Bacteria would be a good answer.
This is one of things that has puzzled me for awhile. Single cell organisms seem to have the advantage in almost all key areas of life. I say this because I believe clearly that there is evidence for it when you look at reproductive rates, the earths bio mass, and adaptablility to almost any conditions on earth. It almost seems that evolution should have stop there.
The argument for multicelluraity is a logical one. Bigger size and division of work seems to be advantegous but the numbers don't really play out that way.
The evolutionary biologist say that multicelluar life has evovled independently 25 times. That seems to me an incredibly low number given the time frame of evolution. The theories of multicellular evolution would also suggest a much easier time to become multicellular and to only have it happen 25 times would suggest a paradox.
Oh I believe its a leap but when looking at the evolutionary timeline its doesn't add up to me.
For instance if the best guess is that life started around 3.8 billion years ago with the earliest fossil records dating from 3.5 billion years ago. Then from that timeline we go from earliest record of viruses from 3 billion years ago but could have been earlier.
Next we go from earliest point of photosynthesis at roughly 2.2 billion years and quickly after that eukaroytic cells at around 2 billion years ago.
The first multicellular life is estimated to occur roughly 900 million to 1 billion years ago. So it took a little less than 3 billion years to go from unicellular to mutlicellular life.
Contrast that from going to multicellular life to the complexity we see today and the evolutionary timeline would suggest that the transition from unicellular life to multicellular life was THE BIGGEST hurdle in evolution.
I have a hard time with that simply by the mutagenesis that would have to occur that would cause a multicellular event. For example some theories suggest and I tend to believe them that a mutagenesis in cytokinesis could have led to forming multicellular life. Now cytokinesis is complex but lets put into perspective here. Is it as complex as forming the eye or even going from a lithrotrophic metabolism to photosynthetic one? I would say no given that the regulatory units and their overlap for controling genetic mishaps would have been less with unevolved/simple lifeforms.
If you believe this publication http://www.nature.com/news/yeast-sug...ar-life-1.9810 then in the lab we can recreate multicellular events in less than 60 days. Now I will be the first to admit that recreating something in the lab doesn't mean this is what happens in nature but it does show that it is plausible to some degree.
Hopefully that gives a better backdrop for why I see a paradox here.
Last edited by Pacerlive; 12-12-2012 at 03:17 PM.
I might just be missing it, because you said it ties in, but I'm not sure what this has to do with Thermodynamics.
"There's no better public education than teaching kids that they should have been born to a parent who could afford their cancer treatments." - @LOLGOP
from Maps of Time by David Christian, the book I am reading right now.Stars can climb the thermodynamic down escalator, but living organisms climb it with greater agility. Indeed, Eric Chaisson has argued that the level of complexity achieved by living organisms can be measured, roughly but quite objectively, by estimating the density of the energy flows that sustain them against the destructive pressure of the second law of therodynamics.
Table 4.1 gives Chaisson's approximations of these energy flows. The right-hand column, which measures the amount of free energy passing through a given mass in a given amount of time, appears to indicate that living organisms can handle far denser flows of energy than stars without breaking down. And this ability is what lets them climb farther and faster up the thermodynamic down escalator. In Schrodinger's famous phrase, each living organism seems to have astonishing capacity for "continually sucking orderliness from its environment". The simplest structures have also been around longest, and the more complex structures have appeared more recently, which suggests that creating them was a more difficult evolutionary task. Finally, it is also clear that the more complex entities in the bottom half of the table are more fragile. While stars and planets may live for many billions of years, even the longest-living organisms (at least those we know of) can live for only a few thousand years, and most live for only a few days or years. That the most complex structures break down so fast is a measure of the difficulty of managing particularly dense energy flows: this is the price living organisms pay for their aggressive challenge to the second law of thermodynamics. Thus in dealing with life we are dealing with a new level of order and complexity, a new capacity to control and organize free energy that is achieved at the price of greater fragility. As Martin Rees has written, "A star is simpler than an insect." But a star also lives there much longer.
I said in relationship to the Toe not necessarily to the second law. To the point of the second law what you said completely makes sense. Its a well argued point that has been regurgitated by many.
Now to the point of probability I would assume what I have stated up above should make sense to most educated people. From the start of the possibility of abiogenesis (start of life) on earth to the time we know we had life it would have been a shorter time than going from unicellular life to multicellular forms. So less time for ambiogenesis to occur on earth than multicellular life?
Does that sound logical to you and if it does please explain it to me.
Now I realize that the Earth had gone through some rough conditions but I would have predicted as a scientist that mutagenesis in basic lifeforms would have occured at a faster rate and in more organisms than what did.
Did evolution have a hiccup?
Do you think that argues for Toe?
Do you think its interesting and is more advantegous to us as posters to consider than these ID arguments against evolution that you are presenting?
In your opening post you said the pursuit of truth was the main goal here or something to that degree and please understand that my intention is not to hijack your thread. Its quite the opposite but these are questions that I have come up with just for funsies and wonder what might the possible answers be because in my mind it doesn't add up.
Last edited by Pacerlive; 12-13-2012 at 07:00 PM.
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