Most of us assume that an equal number of men and women amongst our ancestors. Not so, says John Tierney, writing in the New York Times. He quotes Roy F. Baumeister, who delivered a speech on the subject on Friday at the annual convention of the American Psychological Association in San Francisco. Fear not: Baumeister and Tierney are not suggesting that we re-write the laws of biology.
The article claims that fewer men than women had descendants. This is because men typically have been more adventurous than women. Men go off and fight in wars. Men have built ships and gone off to explore new lands while women rarely did so. A high percentage of these men never had descendants.
In contrast, women generally stayed at home because of social norms and other reasons. As a result, a higher number of women than men raised families. In addition, women throughout history usually died at earlier ages, often in childbirth and sometimes from disease. The widowers often remarried and had additional children. Therefore, a smaller number of men had children by more than one wife.
If you can find every single ancestor in your family tree for the past few centuries, chances are you will frequently see one man appearing multiple times in different limbs of the family tree. You may find him with different wives in your family tree as women will appear less often in duplicate places. When you count up the total number of people you have found in your family tree, chances are that you will find more female ancestors than male.
Interesting thought. You can read more in the New York Times article at http://tinyurl.com/2moo2c.
NOTE: The New York Times has a habit of leaving stories online for only a few days, then removing them. The story is available online as these words are being written, but may not be there for long.
This is indeed an interesting article - and in the grand scope of human history, the hypothesis is probably true. Pedigree collapse is a fact - it has to be, since there were not 1 trillion people on earth 1,000 years ago (that's how many potential ancestors each of us has on our pedigree chart in 40 generations).
However, going back just 400 years to cover the US colonial period and modern history (10 generations - 1024 potential ancestors for each of us), I sincerely doubt that many of us have a man appearing more than once, with different wives, in our fmaily trees. I know I have one that I've found. That doesn't include the same father and mother appearing several times in a pedigree chart - that isn't what the author was discussing.
I've made more comments on my Genea-Musings blog at http://randysmusings.blogspot.com/2007/08/do-you-have-more-women-ancestors.html.
Posted by: Randy Seaver | August 26, 2007 at 11:47 AM
I have a genealogical situation that may be the antithesis of the hypothesis. My father was a POWELL and my mother was a POWELL, although I've found no POWELL connection between them. They are related however, through a common ancestor about 600 years ago! Oddly enough, a young widower with one child remarried and had two more children. His first child was me Mum's ancestor and his third child was me Da's ancestor. All other things being equal, I've one less father than mothers, no?
I still think the overall premise seems sound, and that my case may be in the minority.
Happy Dae.
http://www.ShoeStringGenealogy.com/ssg1.htm
Posted by: Happy Dae | August 27, 2007 at 02:41 AM
Then there are those men who did the honorable / practical thing when first wife died... he married her sister! I have that case, and unless I do a descendants report from him or his ancestors, or from the girls' parents, I would not see it. Both wives had children from him. Hmmm... I guess that's really branching out!
But is the above example the the same case?
What about the following:
My father is my cousin several times over, as is my mother (separate lines). In large families, the eldest child was already having children by the time the younger ones began theirs. This is how this came to pass for me, it began several generations back in colonial times.
Posted by: Peggy LeBlanc | August 27, 2007 at 09:30 AM
This is completely illogical. While a person may have more women than men in a list of all RELATIVES, there will be an equal number of women and men in a list of ANCESTORS. If your tree has several first cousin marriages it would be possible to have more women than men, but also equally possible to have more men than women. I have one branch with several generations of first cousin marriages over 200 years ago and there are still an equal number of men and women in my tree, though fewer individuals. Perhaps in a culture where paternal first cousin marriages greatly outnumbered maternal first cousin marriages the original statement would be true. Also my tree is full of women who outlived more than one husband and had children by two different fathers. However, only one of those husbands can be my ancestor and show up in my family tree. The statement "fewer men than women had descendants" is irrelevant as any man who had no descendants will not show up in anyone's family tree.
Posted by: Vera Zimmerman | August 27, 2007 at 09:51 AM
I don't think the question posed is the important one. What is the genetic variation in the Y gene (from the male in bisexual reproduction) and what is the variation in the mitacondria (from the female contribution in bisexual reproduction)of the gene pool? If there is greater/lesser variation in these two components of our gene pool, why is this so? Are there implications for the composition of the total DNA in the gene pool and, lastly, for male versus female behavior?
Posted by: Jim | August 27, 2007 at 10:22 AM
Let's not forget the guy who was his own Granpa. A gensong by Ray Stevens http://www.mamarocks.com/i_am_my_own_grandpa.htm
Posted by: Chick | August 27, 2007 at 10:39 AM
Well here is the math on my family:
Mother's side of the family
487 female
483 male
Father's side of the family
184 male
196 female
Total
667 males
683 females
2.34% more females
2.3% ain't very significant.
Posted by: Dennis | August 27, 2007 at 11:11 AM
I am not sure if this is accurate or not. My lines are quite intersperced with duel marriages of brother marrying his brothers spouse or lady marrying her spouses brother. I also have many lines of brother and sister whom marry sister and brother and later the two lines marry. I find this fascinating and would be more fascinated by what the DNA and MTDNA people would say about this.
SusiCP
Posted by: Susi | August 27, 2007 at 01:47 PM
I have a hard time accepting the premise that there are simply more men or more women in my direct ancestral pool. My direct ancestral pool requires the participation of one man and one woman to produce a child. That biological fact does not change. As far back as my ancestors can be traced there will be an equal number of men and women to produce each child for each generation. Genetically, each man must produce an X-Y-chromosome and each woman must produce an X-X-chromosome to create offspring. I have never heard, with one exception, of a child being born to only one parent from a genetic point of view. As a result there is only evidence to an equal number of men and women in a genetic line. Now to suggest that there might be more than one woman or one man who was a participant in different levels of the ancestral pool is probably true. But to say that there are more women or more men that I am directly descended from is genetically impossibility.
Posted by: Douglas D. | August 27, 2007 at 03:25 PM
---> But to say that there are more women or more men that I am directly descended from is genetically impossibility.
May I respectfully disagree? I have found two instances of this in my family tree although we all probably have many instances if we could trace our ancestry back a few thousand years.
In my case, two different men had wives who died and then the men remarried, having children by both wives. In each case, I am have multiple lines of descent from the men: at least one line of descent from him and his first wife and then another line of descent from him and his second wife. I am descended from the two men and from their four wives. That's more women than men.
It is also possible to have the opposite: one woman with two or more husbands and a descendant might have at least one line of descent from each husband. However, history shows that it is more common to have a smaller number of men and a larger number of women.
- Dick Eastman
Posted by: Dick Eastman | August 27, 2007 at 03:43 PM
I did a quick check and the numbers for my ancestors are:
615 Male
606 Female
Posted by: Bill Richards | August 27, 2007 at 04:57 PM
In my case I have an ancestor-female- who was widowed and I am descended from that marriage. Her second marriage had children and I am descended from a child of that marriage, too.Two male and one female. It can work both ways.
Posted by: John Carlson | August 27, 2007 at 07:58 PM
"fewer men than women had descendants" -- true. Overall, men have more variation in the number of children they have. It is more likely for a man to have no children than for a woman. (Likewise, some men have far more children than any one woman can have). The greater variation explains why Y-chromosome Adam is a more recent ancestor than mitochondial Eve. Men's lines either die out fast or grow rapidly.
All marriages are marriages between (distant) cousins (pedigree collapse). Because of the gender imbalance, as you work your way up the tree you encounter the same men more often than the same women. So yes, "you are descended from more women than men".
Posted by: Michelle Wilson | September 13, 2007 at 12:24 AM