Saudi Arabia Seeks Union of Monarchies in Region: The conservative monarchy wants to form a single federation with its five Persian Gulf neighbors to better resist the waves of change sweeping the Middle East.
The term “evolution” is pretty broad. One such definition would be self-selective filtering, like only people of certain (genetically determined) personalities moving West to settle the frontier. But is that really evolution? Or just filtering of an existing set? When I think of evolution I think of something “new”. You know, extra eyelids or a missing appendix or a third eyeball at the end of along proboscis. Or more mundanely, the ability to digest grass. Or see a bit further into the infrared.
Is there any example of human evolution of this type in the modern era? It seems that since we can construct our own habitats to our liking, the selection pressure for this sort of thing is indeed nonexistent, so even if some kids were born with the ability to see more infrared, it wouldnt actually give them any evolutionary advantage, and so the trait would get dissolved into the population and never really get selected for.
(I also implicitly define evolution as something tat happens to the entire race, not an individual, so the infrared eyesight example would need to propagate out to the general human public before it would be a valid example of human evolution. One freak with red eyeballs is just a mutation, not evolution).
aziz, if people vary in the number of kids they have, and different types of people vary in the number of kids they have, and different types of people differ because of their genes, evolution is happening. e.g., for example, if believe in god has a heritable component (it does, about 50% of the variance) one could argue it is being selected for in the west.
I think I’m still missing something. At teh risk of creating a totally redundant system of symbols to discuss something I’ve no rigorous training in, and thus proving my ignorance rather than merely implying it, let me define the set of all human genes as G. Thats not just my genome, but yours, and all other humans alive at this very moment. G has some temporal dependence, ie G = G(t) where as time increases, presumably G also does (though it may temporarily suffer a dip in times of extinction).
Now, a single person’s genome would be gi where i = 1…N (N being the human population). So the variance in number of kids, types of people, personalities etc serves just to rearrange genes between gi and gk. Note that offspring genomes are therefore alpha*gi + beta*gk. this is an internal transfer of genes around within G. G is not just the sum over all gi because individuals share genes, so G doesnt grow due to reproduction alone.
Now, I am arguing non-scientifically that G(t) = G0 + Ht^n, where G0 is the genome at some initial point (an arbitrary “start” of te human race), H some constant, and n some exponent. H is probably proportional to the sum of all gi, and n is a measure of the rate of mutation of new genomes, ie genomes that contain genuinely new genetic information.
If the above isnt a pile of garbage, then is it accurate to say that the growth of G over time is slowing down, because the exponent n nowadays is not much greater than zero? Strong evolutionary pressure would increase n because favorable mutations would propagate within G and poor ones would die out.
Is there an email I can use to ask you questions? I’m a student at the University of Florida studying International Relations. I wanted to ask you several questions about this field since you seem very adept and knowledgeable about it. Please give me an email to use if possible!
aziz 8:29 am on October 7, 2008 Permalink |
The term “evolution” is pretty broad. One such definition would be self-selective filtering, like only people of certain (genetically determined) personalities moving West to settle the frontier. But is that really evolution? Or just filtering of an existing set? When I think of evolution I think of something “new”. You know, extra eyelids or a missing appendix or a third eyeball at the end of along proboscis. Or more mundanely, the ability to digest grass. Or see a bit further into the infrared.
Is there any example of human evolution of this type in the modern era? It seems that since we can construct our own habitats to our liking, the selection pressure for this sort of thing is indeed nonexistent, so even if some kids were born with the ability to see more infrared, it wouldnt actually give them any evolutionary advantage, and so the trait would get dissolved into the population and never really get selected for.
(I also implicitly define evolution as something tat happens to the entire race, not an individual, so the infrared eyesight example would need to propagate out to the general human public before it would be a valid example of human evolution. One freak with red eyeballs is just a mutation, not evolution).
aziz 8:29 am on October 7, 2008 Permalink |
why yes, I am completely untrained in evolutionary science. You need to write a book, Razib.
razib 1:09 pm on October 7, 2008 Permalink |
aziz, if people vary in the number of kids they have, and different types of people vary in the number of kids they have, and different types of people differ because of their genes, evolution is happening. e.g., for example, if believe in god has a heritable component (it does, about 50% of the variance) one could argue it is being selected for in the west.
aziz 2:31 pm on October 7, 2008 Permalink |
I think I’m still missing something. At teh risk of creating a totally redundant system of symbols to discuss something I’ve no rigorous training in, and thus proving my ignorance rather than merely implying it, let me define the set of all human genes as G. Thats not just my genome, but yours, and all other humans alive at this very moment. G has some temporal dependence, ie G = G(t) where as time increases, presumably G also does (though it may temporarily suffer a dip in times of extinction).
Now, a single person’s genome would be gi where i = 1…N (N being the human population). So the variance in number of kids, types of people, personalities etc serves just to rearrange genes between gi and gk. Note that offspring genomes are therefore alpha*gi + beta*gk. this is an internal transfer of genes around within G. G is not just the sum over all gi because individuals share genes, so G doesnt grow due to reproduction alone.
Now, I am arguing non-scientifically that G(t) = G0 + Ht^n, where G0 is the genome at some initial point (an arbitrary “start” of te human race), H some constant, and n some exponent. H is probably proportional to the sum of all gi, and n is a measure of the rate of mutation of new genomes, ie genomes that contain genuinely new genetic information.
If the above isnt a pile of garbage, then is it accurate to say that the growth of G over time is slowing down, because the exponent n nowadays is not much greater than zero? Strong evolutionary pressure would increase n because favorable mutations would propagate within G and poor ones would die out.
Nora 8:09 pm on September 30, 2009 Permalink |
Salam Br. Aziz,
Is there an email I can use to ask you questions? I’m a student at the University of Florida studying International Relations. I wanted to ask you several questions about this field since you seem very adept and knowledgeable about it. Please give me an email to use if possible!