dttom Posted December 15, 2009 Posted December 15, 2009 Early in the human history, when the individual could hardly be rendered as human by modern standard, wars or conflicts between tribes were usual. The idea that a member should contribute the tribe but not the rivaling tribe was necessary for sustaining the glory of a tribe. This resulted in the basis for the religion that a member should have as little relationship with a member from other opposing tribes. Punishment was expected for those who betrayed this meme. Under such a condition, a member who remained ‘loyal’ to his tribe would be credited and the opposite would be disregarded, and this would easily favor the emergence of gene, if any, which distinguished between members of his own tribe and those of the opposite, as one could be innocently punished by accidentally recognizing ‘foreign’ as ‘self’. With the emergence of such a gene, or genes, the accident rate and innocence were expected to decrease, though such genes could confer virtually no benefit for those who were loyal, yet they could still spread through genetic drift. Coupled with civilization, such a meme declined, yet the ‘loyal’ genes persisted. This could be one of the results of the differential emergence rates between memes and genes, both being an element in respective evolution. Such a ‘loyal’ gene would instinctively suggest a person to favor ‘self’, or of his own kind, which simultaneously and relatively suggest disfavoring ‘non-self’ or other kinds. The word ‘self’ in ancient time was defined as members in a tribe which the individual belonged to, and this gene worked by allowing an individual to recognize characteristics shared amongst members within the same tribe yet not possessed by those outsiders; inferring its meaning it could easily mean the individuals sharing the same recent ancestry with the possessing individual. Such an ancestry would surely be very recent. Yet would this form the basis for the especially irritating race issue is an open topic for discussion, though until today there has not been a gene identified for ‘discriminatory’. Another separate example in this issue is related to insects. In some species of insect imprinting plays a determining role in the food source which the larvae and the grown-up adult would eat by selecting the location where to lay the eggs. For an individual accidentally laying eggs in a ‘wrong’ location could drive an offspring lineage to a different food source. Because of difference distribution of food, this accident could become a sympatric barrier and drive the subsequent genetic evolution. The process of imprinting is definitely not a genetic one, the action would not change even a tiny bit in germ-line genome; if considering it as epigenetic would also be sensible as the process should at least involve some changes in cell connection, signaling or synthesis in chemicals in vivo; yet it would also make sense if treating it as a kind of vertical meme base on the same logic, meme propagation should provoke some in vivo change for it to function, as no signal could transmit without contact.
jake.com Posted December 16, 2009 Posted December 16, 2009 In some species of insect imprinting plays a determining role in the food source which the larvae and the grown-up adult would eat by selecting the location where to lay the eggs. For an individual accidentally laying eggs in a ‘wrong’ location could drive an offspring lineage to a different food source. Because of difference distribution of food, this accident could become a sympatric barrier and drive the subsequent genetic evolution. i'm not so sure about this part. A new species would require genetic change. this would assume that the 'accidental' children didn't slowely die away. this would also assume that there were enough individual to carry on the trend. how would this small gene pool prevent an inbreeding nightmare? the only animal i think this could work for would be a butterfly (more specifically a caterpillar), since their larval stages do have significant changes within a single species. But this would bring up a sympatric barrier, since the adults still look the same. so.... i don't know.
dttom Posted December 16, 2009 Author Posted December 16, 2009 You remind me that there is a circumstance that the food source which the usual individuals choose is completely alternative, that choice on other food source would not result in lowering in fitness, except, if it is a social species the alternative food source would, if any, posed some social barrier which lowers its competivity. And the inbreeding issue, I think there should be, and to a certain degree is a must accompanying to any speciation event. The founder effect based on geographic isolation would still meet the same problem. But of course, any speciation is the result of the sucessful passing through of such a bottleneck. Going through such an event relatively short ago is also why the human genome diversity is limited compared with other species.
jake.com Posted December 16, 2009 Posted December 16, 2009 And the inbreeding issue, I think there should be, and to a certain degree is a must accompanying to any speciation event. The founder effect based on geographic isolation would still meet the same problem. But of course, any speciation is the result of the sucessful passing through of such a bottleneck. But founder's effect only works if there's enough specimens to survive the inbreeding. Thats the point i was trying to make.
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