The One Drop Rule

[bugstud]

I would imagine that indigenous new guineans, aborignes, inuit and what few african and native american tribes are left would dispute your 600-800 years claim.

most the other stuff you cite is more or less accepted, but your assertion here seems off base to me.

[M.B.E.]

Christina's statement, "Except the most culturally isolated areas, everyone is descended from common ancestors of about 600 to 800 years ago", is not crazy at all, although the figure might be a little too low. Population geneticists have been modelling this in the last couple of years, and have concluded that the most recent common ancestor (MRCA) of all humans alive today (including isolated groups) most likely lived about 76 generations ago, or 2,300 years before present.

Here are some links:

Article in Nature magazine (pdf)

The Loom: Bloodless Bloodlines and other Genealogical Paradoxes

The Loom: More on Common Ancestors

On the common Ancestors of All Living Humans (pdf)

[M.B.E.]

[ QUOTE ]
i read this book that said geneticists have found that all humans alive today come from a group of about 100,000 people in one region of africa. wish i had the book in front of me to drop some proper science, but i'm at work.

[/ QUOTE ]
Actually, it is estimated that all humans are descended from a population of about 20,000 hominids:

Rannala B, Yang Z (2003) Bayes estimation of species divergence times and ancestral population sizes using DNA sequences from multiple loci. Genetics 164: 1645-1656.

Article in the journal Genetics (pdf)

This may be why there are so many genetic diseases in humans, as compared to other mammal groups like mice and rats that did not have an equivalent "population bottleneck":

http://www.bath.ac.uk/pr/releases/hominidgenomes.htm

The research was announced a couple of weeks ago.

[peachy]

I never said that we werent from the beginning of time...but sayin we all r from as little as 800 yrs ago is nuts. And saying that we r all related to royalty from 800 yrs ago is further nuts because now you have just narrowed down the possible linage by a fraction of the whole population of that time. It just isnt possible at this present time, maybe in another 1000 years

[Grivan]

Well lets see 4 genereations in 100 years, each person has 2 direct ancestors, so 100 years back they have 14 direct ancestors, and 800 years back they have approximatly 1.5 billion direct ancestors by this direct method (ignores duplication so is high). Now realizing that the population of Europe in 1200 was significantly less then 100 million, I don't think Christina's argument is really that much of a stretch.

[peachy]

ur assuming everyone "got it on"...therefore ur math is a lil wrong...like i said...im not sayin were not all related somehow from way back when...im disputing the fact that EVERYONE is linked to royalty within the past 800 years

[M.B.E.]

[ QUOTE ]
And saying that we r all related to royalty from 800 yrs ago is further nuts because now you have just narrowed down the possible linage by a fraction of the whole population of that time.

[/ QUOTE ]
Peachy, give us your estimate. Approximately what percentage of humans alive today are directly descended from royalty who lived within the last 800 years?

[Grivan]

Im not assuming everyone got it on Im assuming everyone who had a kid got it on. Notice how I started at 1 person and assumed everyone had 2 parents. People that never had kids never even come into play.