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Quote (Douglas @ Sep. 27 2009,08:23) Quote (Stu @ Sep. 26 2009,07:26) Because it is not true. Humans have always been a medium to large group, ever-changing. If you went back in history you would not be able to identify the ‘first human’, because ‘human’ is just a name for an evolutionary stage of a whole population.
It doesn't alter your basic argument any, but I believe there's some evidence for the possibility that the human race has been to the relative brink of extinction at least once in the past – so the total population size hasn't always been that large.A species originating from only 1 breeding pair however would rapidly become inbred without a very good genetic strain. It would be somewhat incestuous too!
My memory is of a general bottleneck value of 1000 as the minimum population size from which any species could recover, although obviously there would be variation between species.I must look for a reference for that.
Stuart
Quote (Stu @ Sep. 27 2009,15:57) Quote (Douglas @ Sep. 27 2009,08:23) Quote (Stu @ Sep. 26 2009,07:26) Because it is not true. Humans have always been a medium to large group, ever-changing. If you went back in history you would not be able to identify the ‘first human’, because ‘human’ is just a name for an evolutionary stage of a whole population.
It doesn't alter your basic argument any, but I believe there's some evidence for the possibility that the human race has been to the relative brink of extinction at least once in the past – so the total population size hasn't always been that large.A species originating from only 1 breeding pair however would rapidly become inbred without a very good genetic strain. It would be somewhat incestuous too!
My memory is of a general bottleneck value of 1000 as the minimum population size from which any species could recover, although obviously there would be variation between species.I must look for a reference for that.
Stuart
That would be interesting. Assuming it's factually accurate Wikipedia has: http://en.wikipedia.org/wiki/Population_bottleneckThough the elephant seal figure doesn't agree with the elephant seal page. I think theoretically a species could go underneath whatever limit you find – but would be at far greater risk of being wiped out by disease or weaknesses inherent in the gene pool until enough diversity had returned through natural variations (a rather slow process).
I seem to recall the genetic ancestry of Europeans comes from a rather limited number of individuals.
Anyway, would be interested in any references to any definite limiting point.
stu- no God isnt sending you to hell ,YOU send your self by not excepting him as your Saviour. God knows the heart and He knows if you mean it when you ask Him into your life. And why dont you feel any of this, its because you will not except Him!! He does not enter until you ask. we have a choice to live with him in our lifes or without, and if you dont want to except Him after He sacrificed His life for you why would you expect Him to save you from hell?
katjo
Quote no God isnt sending you to hell ,
I know. Hell and god are made-up fantasy tales.Quote YOU send your self by not excepting him as your Saviour.
Have you just been to church?Quote God knows the heart and He knows if you mean it when you ask Him into your life.
You have been to church. How long does it usually take you to get back to being a charming, civil human being with a genuine interest in other people, instead of lecturing at them?Quote And why dont you feel any of this, its because you will not except Him!!
No, the reason I do not accept it is because it is all fictional.Quote He does not enter until you ask.
Would you care to rephrase that?Quote we have a choice to live with him in our lifes or without, and if you dont want to except Him after He sacrificed His life for you why would you expect Him to save you from hell?
I do not expect non-existent people to save me from things that do not exist. That is just silly.Come back when you have calmed down, and maybe we could resume a pleasant conversation.
Stuart
Quote (Douglas @ Sep. 28 2009,10:21) Quote (Stu @ Sep. 27 2009,15:57) Quote (Douglas @ Sep. 27 2009,08:23) Quote (Stu @ Sep. 26 2009,07:26) Because it is not true. Humans have always been a medium to large group, ever-changing. If you went back in history you would not be able to identify the ‘first human’, because ‘human’ is just a name for an evolutionary stage of a whole population.
It doesn't alter your basic argument any, but I believe there's some evidence for the possibility that the human race has been to the relative brink of extinction at least once in the past – so the total population size hasn't always been that large.A species originating from only 1 breeding pair however would rapidly become inbred without a very good genetic strain. It would be somewhat incestuous too!
My memory is of a general bottleneck value of 1000 as the minimum population size from which any species could recover, although obviously there would be variation between species.I must look for a reference for that.
Stuart
That would be interesting. Assuming it's factually accurate Wikipedia has: http://en.wikipedia.org/wiki/Population_bottleneckThough the elephant seal figure doesn't agree with the elephant seal page. I think theoretically a species could go underneath whatever limit you find – but would be at far greater risk of being wiped out by disease or weaknesses inherent in the gene pool until enough diversity had returned through natural variations (a rather slow process).
I seem to recall the genetic ancestry of Europeans comes from a rather limited number of individuals.
Anyway, would be interested in any references to any definite limiting point.
Looks like the Holy Wikipedia might be putting the lie to my figure of 1000.Isn't that interesting about cheetahs and skin grafts.
Stuart
Quote (Stu @ Sep. 28 2009,18:06) Quote (Douglas @ Sep. 28 2009,10:21) Quote (Stu @ Sep. 27 2009,15:57) Quote (Douglas @ Sep. 27 2009,08:23) Quote (Stu @ Sep. 26 2009,07:26) Because it is not true. Humans have always been a medium to large group, ever-changing. If you went back in history you would not be able to identify the ‘first human’, because ‘human’ is just a name for an evolutionary stage of a whole population.
It doesn't alter your basic argument any, but I believe there's some evidence for the possibility that the human race has been to the relative brink of extinction at least once in the past – so the total population size hasn't always been that large.A species originating from only 1 breeding pair however would rapidly become inbred without a very good genetic strain. It would be somewhat incestuous too!
My memory is of a general bottleneck value of 1000 as the minimum population size from which any species could recover, although obviously there would be variation between species.I must look for a reference for that.
Stuart
That would be interesting. Assuming it's factually accurate Wikipedia has: http://en.wikipedia.org/wiki/Population_bottleneckThough the elephant seal figure doesn't agree with the elephant seal page. I think theoretically a species could go underneath whatever limit you find – but would be at far greater risk of being wiped out by disease or weaknesses inherent in the gene pool until enough diversity had returned through natural variations (a rather slow process).
I seem to recall the genetic ancestry of Europeans comes from a rather limited number of individuals.
Anyway, would be interested in any references to any definite limiting point.
Looks like the Holy Wikipedia might be putting the lie to my figure of 1000.Isn't that interesting about cheetahs and skin grafts.
Stuart
Well, it's still a good general rule that as the available genetic diversity within a species diminishes it's ability to adapt to varying conditions will also diminish – and raise the risk of extinction.That said, species on the edge of extinction often also undergo more rapid evolution (refer Tasmanian devils, and cod, for examples). Presumably because the ones which aren't extinct are very heavily under selective pressure (even if just by not being extinct with the rest of their species).
I think it also depends how specialised a species has let itself become – rats are sufficiently versatile that even a small number probably could recover, something that eats only bamboo shoots on the other hand – is in deep trouble if the bamboo goes…
And I imagine it also depends of course on how homogenous the genetic mix is in whatever size of population. A population of tens of genetically diverse individuals could outperform hundreds of very genetically similar individuals I daresay.
I suppose there would be a brake on this too: opposites do attract, but eventually there must be a point where the large diversity of the small population is less useful because the large differences might be a barrier to mating.
I read a while back of the discovery of a kind of 'holder' protein, I think it was in insects, which was able to hold other functional proteins in the correct shape even if they had been affected by a mutation that would have otherwise rendered them inactive. The effect of the holder proteins was to mask the mutation, but those proteins were the first thing to not be produced in times of stress. Without the holders, all those hidden mutations would be suddenly expressed, at a time when genetic variation was most needed.
Stuart
Quote (Stu @ Sep. 25 2009,00:33) There's no such thing as sin at all, except that invented by the religious. We can all do far better without that concept. Why do some have to cast their minds slavishly into such anti-human nonsense?
Stuart
Greetings Stu……Sin is the transgression of the law…Transgression of law is self explanatory…The religous emphasis speaks to Gods law,which, if you examine it carefully you see that our civil laws are similar with the exception that man decided to add to and in some cases change…..As an example lets take Murder….Gods law forbids murder and specifies death as the consequence….Our law changed the terminology to Kill….and with that we warehouse thousands of persons who have murdered more than once in our prison system…..So we won't call it sin..Let us call it crime so as to eliminate any religous conotation…..FOOLISHNESS !!!Quote (theodorej @ Sep. 30 2009,20:25) Quote (Stu @ Sep. 25 2009,00:33) There's no such thing as sin at all, except that invented by the religious. We can all do far better without that concept. Why do some have to cast their minds slavishly into such anti-human nonsense?
Stuart
Greetings Stu……Sin is the transgression of the law…Transgression of law is self explanatory…The religous emphasis speaks to Gods law,which, if you examine it carefully you see that our civil laws are similar with the exception that man decided to add to and in some cases change…..As an example lets take Murder….Gods law forbids murder and specifies death as the consequence….Our law changed the terminology to Kill….and with that we warehouse thousands of persons who have murdered more than once in our prison system…..So we won't call it sin..Let us call it crime so as to eliminate any religous conotation…..FOOLISHNESS !!!
Just before you take all the credit for your religion, just remember that while Judeo-christianity has only existed for the last 5% of human history, ethics and legal codes have almost certainly been in existence for a much greater time than that.Don't think the ancient Jews were the first to think of these things.
Stuart
But he is a latecomer. Humans have been around a lot longer that the Judeo-christian god. Why shouldn't he wait in the queue like everyone else?
Stuart
Quote (Stu @ Sep. 29 2009,16:56) I suppose there would be a brake on this too: opposites do attract, but eventually there must be a point where the large diversity of the small population is less useful because the large differences might be a barrier to mating. I read a while back of the discovery of a kind of 'holder' protein, I think it was in insects, which was able to hold other functional proteins in the correct shape even if they had been affected by a mutation that would have otherwise rendered them inactive. The effect of the holder proteins was to mask the mutation, but those proteins were the first thing to not be produced in times of stress. Without the holders, all those hidden mutations would be suddenly expressed, at a time when genetic variation was most needed.
Stuart
Yes, of course there is a brake – it's the point at which a species has diverged so much it's now two species (not all members able to interbreed with all other members). I suspect that generally happens before physical differences become particularly extreme.The protein is an interesting idea, if it enabled variety to be expressed more when useful. Any references for it, and did it just apply to insects?
So with all those people with power, why is there any darkness. Do they actually NOT have power over it, or do they not care about it?
Stuart
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