In Chapter I of "The ancestor's Tale, Dawkin's states that first we must not assume if a person is related to another person from the distant-past, that my neighbor is also related to the same distant ancestor as me. Dawkin's notes, that there is no way of knowing how far back in time that when using "genetic trees" would still not lead you to the "most recent common ancestor" (MRCA); because you do not know how far to go back in time (Dawkin, p. 40-41).
Dawkin's also states, that we do not know how "ancient" is ancient enough, that an individual that has any human genes and offspring must be the oldest ancestor of all humans to come after (Dawkin, p. 39).
2. Dawkin's refers to "mitochondrial Eve" is that all females have Eve's mitochondrial DNA (Eve is supposed to be the first woman of the Earth to those "faithful); and all female descendants bare her genes. But, this can be misleading to assume because Eve could have had several lovers and many different genetic diversities of her offspring according to Dawkins (pp. 54-55). Adam could also lived years after Eve passed away or he could have interbred with other individuals too; and Dawkin's states that all of Adam's male descendants will have all of Adam's Y chromosome information (because only a male has an XY chromosome). In addition, Dawkin's states that male's do have mitochondrial DNA, but they do not pass it on to any male or female offspring (Dawkins, pp. 54-55).
The "Out of Africa" hypothesis or theory is that all humans came or descended from Africa, when the land continents were one-continous land mass (Pangea); and the humans' left Africa and migrated to distant lands and interbred with new populations, according to scientists 100,000 YA. But, this theory is highly debated because of "population bottlenecks" and fossil evidence.
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Good entry. Dawkins does talk about however how Templeton uses many genes to predict that there are 3 different migrations out of africa which he favors the most.
ReplyDeleteI am glad that you added in about them having more than just one partner. So we do have many different varieties of genes that do make us up.
ReplyDeleteYes, those are also items that Dawkins warn us about.
ReplyDeleteHe also mentioned not to think that history woks to deliver the present (the hindsight concept) and that we should be cautios associating patterns in evolutionary biology with directional evolution forming the great chain of life.
Yes, Kelly Templeton did describe the three migrations out of Africa and that is very plausible too and either Asia as well.
ReplyDeleteI totally agree G.C. that the "great chain of being or life" isn't the whole theory behind evolution and really in our scientific infancy who really knows the evolutionary past, yet?
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