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I went back and looked at a website or two and found this:
The type of cousin-ness can be important in terms of heredity and consanguinity if first cousins marry.
I don't agree with this at all. If person A and person B are first cousins, they share one set of grandparents, whether the sibling parents are male or female. Consequently, the genetic contributions of the grandparents is going to be the same regardless of the "type of cousin-ness."
Unless there is something about genetics and eugenics (in the positive sense of the word of course) that has changed since I took a course in genetics back in the dark ages.
While this is taking a wonderful word thread and possibly diverting it to things non-word related, I guess it's OK because I am asking why the words exist at all.
If someone wants to take this discussion to private messages feel free to do so.
TEd
TEd
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Well, what Fong aptually said was "We never used the term orthocousin" - but tsuwm's OED quote cleared up the twin terminology anyway.
The site you initially referenced, TEd, gave the same info on genetics, noting that their source material was old fashioned and had been superceded by more modern research based on DNA spread.
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I don't agree with this at all. If person A and person B are first cousins, they share one set of grandparents, whether the sibling parents are male or female. Consequently, the genetic contributions of the grandparents is going to be the same regardless of the "type of cousin-ness."
Consider there are certain traits passed on from mother to daughter via mitochondrial inheritance. If Female1 (with mitochondrial DNA A) (F1a) and Male1 (with mitochondrial DNA B) (M1b) have three children, two girls and one boy, all of the children will have mitochondrial DNA A: in other words F2a, F3a, and M2a.
If F2a and F3a have children with non-related males, who have mitochondrial DNA y and z, respectively, (M3y and M4z) their children will still have mitochondrial DNA A.
If M2a, the one brother of F2a and F3a, has children with a non-related female, with mitochondrial DNA X, M2a’s children will have X mitochondrial DNA and not A.
Further consider that if 1st, 2nd, 3rd, or 4th cousins, etc., who all have mitochondrial DNA A, and a history of a trait being passed via mitochondrial inheritance, get married and have children, the children will get a double dose, so to speak of the trait.
I’m not sure, but I think mutation would lessen the trait as the generations progressed though.
That written, mitochondrial inheritance wouldn’t exclusively relate to orthocousins though. Nevertheless, one would think that there should be a term for mitochondrially related cousins.
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Not a bit of this was touched upon when I took genetics back in 1965 or 66. I can see from what you say there is importance in the ortho/cross cousin differentiation. It also makes one think about those societies that were ()or are I guess) matrilinear. Like they knew something!
TEd
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I'm wondering if the forbidden-marriage thing had something to do with ideas of where babies came from? There was, for example, a theory that the child actually came from the man, and the woman was no more than a place to grow it. In light of that, cross-cousins wouldn't be considered related, as their fathers would be different. But then ortho-cousins whose mothers were sisters should also be OK...hmmmm....
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Consider there are certain traits passed on from mother to daughter via mitochondrial inheritance
If these traits are passed from mother to doughter why would this affect males? Seems like the only marriagges we should disallow are marriages between dughters of sisters. And even then I shouldn't think we'd need worry about their children.
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Did we know about mitochondrial DNA in the 60s? I remember reading genetics texts in 1967 that showed white and black guinea pigs having different combinations of white and black babies. Later I bred angora rabbits and realized how many colours hide behind dominant black and albinism. Those damn guinea pigs lied!
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If these traits are passed from mother to doughter why would this affect males? Seems like the only marriagges we should disallow are marriages between dughters of sisters.
Writing in regards to mitochondrial inheritance only, as I understand it, mitochondrial DNA is passed by the mother to all of her children, male and female. Only the daughters, however, can pass the mitochondrial DNA on; the males cannot. Nevertheless, it is possible for a male and a female who share the same matrilineal great, great, great, great, great (etc.) grandmother, but descended through different matrilineal lines, i.e., through different daughters of the original matriarch, to have the same mitochondrial DNA. But, as I mentioned earlier, mutation would become more and more evident as the generations progressed.
Apropos: if I’m not mistaken, recent research into the pace of mutation in mitochondrial DNA, by testing a broad cross-section of humans, indicates that there was a dramatic decrease in the world population of Homo sapiens, at some point in the not-too-distant evolutionary past, from millions, down to a few thousand (or perhaps less than a thousand – I’d have to look it up). I’m probably wrong, but I think the research indicates that the decrease happened around 65,000 years ago.
genetics texts in 1967 that showed white and black guinea pigs having different combinations of white and black babies. Later I bred angora rabbits and realized how many colours hide behind dominant black and albinism. Those damn guinea pigs lied!
Hello, Elizabeth, and welcome!
If I recall correctly, the recessive gene traits account for your “in living color” bunnies.
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It's not just recessive traits, Dgeigh, it's that we track five different genes in rabbits - Agouti/non-agouti, Black/brown, colour distribution, dilution, extension. I once had three black rabbits, one of whom was black, one white and one red. Disraeli expressed the black dominant gene. Lily was genetically black (which I knew because when I bred her to a brown buck, she produced black babies), but expressed the gene for albinism, so looked white. Jonquil was genetically black, but had the extension gene that said "all this eumelanin will be phaeomelanin" - translation, black colour will become yellow(red). So he looked red, although genetically he was black. It could take me five generations to be sure of some colours in a particular bunny, especially when some things didn't show up until the bunny was three or four years old (like "steel" - white tipping on black). Oh, yeah - I know a lot about colour in bunnies and sheep, and I know that if you breed two black rabbits, two white rabbits, or one black and one white, there's no telling what you'll get, at least the first time out. So I repeat - those texts lied, because they never showed all that recessive stuff.
But it was fun, and I liked the bunnies.
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Pooh-Bah
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I read an interesting book on this topic recently, but I couldn't remember the title. A friend kindly reminded me. Since his email mentioned a few other books that may be of interest, I've quoted the relevant paragraph in full. I have assumed his permission to do this. Another book, which I only perused, "Guns, Germs and Steel," by Jared Diamond, suggests that the claim of the importance of matrilineal (mitochondrial) DNA has been *somewhat* debunked, but the passage concerning this did not say how, who, or why.
The book I think you are referring to is called "The seven daughters of Eve." by Brian Sykes. I don't remember recommending it as I have not actually read this particular book. Related reading that I do know is "The Journey of man" by Spencer wells which traces the human Diaspora via the Male chromosome rather than mDNA. For technical reasons (which he explains) you get a finer detail from this method. His book is rather popular, a companion to a PBS offering but still informative and a quick read. And if you haven't read it already "Genome" by Matt Ridley is a superb overall look at what our genes can tell us about our evolutionary past and well worth reading (as are any of his other books. for example I just finished "The agile gene" his latest, which is an stimulating philosophical discussion of the current academic wars over nurture versus nature. The original title in England was "Nature via Nurture" by for obscure reasons the American publisher decided to change it.)
"Seven Daughters" attempts establish seven major genetic populations globally, by tracing their mitochondrial DNA to seven women descended from a single woman who passed out of -- is it the "Horn" of Africa -- perhaps (and I may be mistaken) 200,000 years ago. That there were 7 women is arrived at by deduction, and, in that since, they are only hypothetical. However, if the theory is true, seven such women did actually exist, and we are each decended from one of them. It is like the question of who Homer was: Homer was whoever wrote "The Odessy." A question which, differently phrased, is similar in form, is not analogous to "Who wrote Shakespeare?" But I digress.
Speaking of drama, urgency is added to deliberations by imprisonment: I speak of the jury's own.
Edit: "Seven Daughters" was published in 2001; "Guns, [etc.]" was published in 1997
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