Rare 'goat-sheep' born on Irish farm • Hacker News Board

Re: Rare 'goat-sheep' born on Irish farm

#111

Post by Houshalter » Sun, Apr 06, 2014, 8:03 PM UTC

spullara wrote: post #108

Houshalter wrote: post #101

Earlier quoted context omitted.

Yes actually. Here is an explanation why. http://dgmweb.net/Ancillary/OnE/NumberAncestors.html

It is obviously false. There are many people that were alive 1000 years ago that you have no relation to due to geographic separation. Just because you can analyze something using statistics doesn't make it right. It even explains some of the discrepancy in the description of that chart — your ancestors are not unique and therefore the entire chart is just statistical hyperbole.

I said almost everyone, obviously you aren't (likely) related to remote islanders. However you'd be surprised how much mixing there is between population. All you need is one individual from another population to mix with another and within a few generations he is everyone's ancestors.

I'm not certain how much mixing there was between the new and the old world. However it did happen a lot and it's likely a large number of people do have some new and old world ancestors.

Re: Rare 'goat-sheep' born on Irish farm

#112

Post by maxerickson » Sun, Apr 06, 2014, 8:21 PM UTC

Houshalter wrote: post #111

spullara wrote: post #108

Earlier quoted context omitted.

It is obviously false. There are many people that were alive 1000 years ago that you have no relation to due to geographic separation. Just because you can analyze something using statistics doesn't make it right. It even explains some of the discrepancy in the description of that chart — your ancestors are not unique and therefore the entire chart is just statistical hyperbole.

I said almost everyone, obviously you aren't (likely) related to remote islanders. However you'd be surprised how much mixing there is between population. All you need is one individual from another population to mix with another and within a few generations he is everyone's ancestors. I'm not certain how much mixing there was between the new and the old world. However it did happen a lot and it's likely a large numb…

You are overstating the amount of mixing between populations (and somewhat discounting the mixing within populations).

1000 years ago, people in villages and towns were regularly marrying their (2,3,4) cousins and rarely marrying people from 'different lands'.

Another way to look at it: for 1 person to become the ancestor of just several thousand people takes 'a few generations'. Getting to whole populations takes lots of generations.

Re: Rare 'goat-sheep' born on Irish farm

#113

Post by maxerickson » Tue, Apr 08, 2014, 1:46 PM UTC

Houshalter wrote: post #74

Steuard wrote: post #60

Earlier quoted context omitted.

I saw that claim in the article, yes. I'll admit that I don't know enough about genetics to make strong claims here, but it doesn't sound remotely plausible to me. He wants to simultaneously claim that 1) hominids got so much porcine DNA that they have lots of substantial, recognizable anatomical features as a result, and 2) hominids have so little porcine DNA that it's all but invisible in our genetic code. I'm not…

I don't see why it's that implausible. You are descended from almost every single human being alive 1,000 years ago. Can you find any significant amount of DNA contributed from only a single one of your ancestors? What he is suggesting is that a single hybrid made it's way back into the hominid population. It had children with other hominids, and those children would have had half as much pig DNA. They had children w…

I submitted the article I link in a subthread here:

https://news.ycombinator.com/item?id=7539143

The author posted some replies, one of which points to this article:

http://phenomena.nationalgeographic.com/2013/05/07/charlemag...

That puts it at about 3400 years (the article gets the number from some paper on the topic).