How many ancestors do you have

[Peterski]

Interesting blog articles:

https://thewildpeak.wordpress.com/20...s-do-you-have/

https://blog.kittycooper.com/2014/05...000-years-ago/

[rothaer]

Interesting blog articles:
https://thewildpeak.wordpress.com/20...s-do-you-have/
https://blog.kittycooper.com/2014/05...000-years-ago/

That's all essentially applicable.

An other important aspect is not mentioned and this motivates some people to say: We have all the same ancestors, hence the same ancestry.

We likely can already sense that this is not really applicable. Why are we then regionally different? Because the main difference between people is not whether they have a particular ancestors at abt. 1000 AD or 800 AD or not, but how often they have him, 1 time or 20,000 times (lineages connecting).

[rothaer]

In this context this is also interesting:

The chance that you do inherit nothing from a particular ancestor 10 generations ago is abt. 50%.
The chance that you do inherit nothing from a particular ancestor 13 generations ago is abt. 90%.

https://gcbias.org/2013/11/04/how-mu...ular-ancestor/

[rothaer]

So out of the number of genealogical ancestors only some are also genetical ones. It can be imagined to look like this f. i.:

[Brás Garcia de Mascarenhas]

What an odd coincidence but in one of the books I am currently reading (The Elixir of Immortality) there is a paragraph\dialogue that mentions exponential growth from a genealogical perspective.

- Listen to me, boys, and I'll give you a lesson on exponential growth. Listen carefully and think about what I say.

I had four grandparents. When we go back five generations, in other words, to the era of the French Revolution, the number rises to one hundred and twenty. And consequently, around 1630, I had sixteen thousand three hundred and eighty-two. If you go back even further in time, to the beginning of the fourteenth century, that is, thirty generations ago, I had one thousand ninety million, one hundred and twenty-five thousand, eight hundred and twenty-four ancestors.

Are you following me?
That means that you had at least four thousand three hundred and sixty million, five hundred and three thousand, two hundred and ninety-six ancestors.

[Hektor12]

Small, isolated populations such as those of remote islands represent extreme examples of pedigree collapse, but the common historical tendency to marry those within walking distance, due to the relative immobility of the population before modern transport, meant that most marriage partners were at least distantly related. Even in America around the 19th century, the tendency of immigrants to marry among their ethnic, language or cultural group produced many cousin marriages.

YEP..

And..

If one considers as a function of time t the number of a given individual's ancestors who were alive at time t, it is likely that for most individuals this function has a maximum at around 1200 AD. It was suggested in 1985 that everyone on Earth is at most 50th cousin to everyone else, based on a relatively random mating model.[5] Simulations published in 2004 which take into account the geographical separations and less random patterns of mating in real life suggest that some populations are separated by up to a few thousand years, with a most recent common ancestor perhaps 76 generations back, though some highly remote populations may have been isolated for somewhat longer.[6][7]

https://en.wikipedia.org/wiki/Pedigree_collapse