Mark Stauter (
16 Jan 1995 22:13:03 GMT

Warren Lathe ( wrote:
: In <3feamc$> (Daniel A Ashlock) writes:

: >In article <3fe9e6$>, writes:
: >>How can we possibly have more ancestors in a coexisting generation than
: >>the total known population of the earth?
: >>
: >>I know for a fact that I have a mother and a father who each has a mother
: >>and a father, etc... The direct ancestral chart would look like so:
: >>Generation Population
: >>1 2 (Mother and father)
: >>2 4 (grandparents)
: >>3 8 (greatgrandparents)....
: >>20 1,048,576
: >>30 1,073,741,841
: >>Going backwards it does not take too long to run into a problem.

: > You are counting individual people multiple times. I think your
: >incest taboo is way too strong.
: >--
: >Dan Ashlock

: Yes, he is right. I am an avid geneologist. THe further back I go the more
: cousins and other relatives I find married to each other. That is true
: of most family lines. It wasn't so much a taboo generations ago, in fact
: it was encouraged in many families and cultures (though sibling marriage
: has been generally taboo through cultures and time). So, in other words,
: those lines converge. The numbers don't grow exponentially as you thought.

: Trey

: _________________________________________
: Warren C. Lathe III
: Biology Department
: University of Rochester
: email:
: _________________________________________
: --
: The juvenile seasquirt wanders through the sea searching for a suitable rock
: or coral to cling to and make its home for life. For this task it has a
: rudimentary nervous system. When it finds its spot and takes root, it
: doesn't need its brain anymore so it eats it.It's rather like getting tenure.

Just for the record, it's called "pedigree collapse," and is very well
known in the fields of genealogy, population statistics, etc.

Mark S.