Comments on Gauger Single-Couple Human Origin is Possible

Their wording is confusing. Are they arguing for a bottleneck of two people or that it’s possible only two Homo sapiens evolved? Is this just her bottleneck model but more developed?


Paper won’t load for me :confused:

This is Earth shattering - Bio-Complexity Journal published its first paper of the year! And GAE could have been H. Erectus.

ITs not YEC but its helpful. i’m sure all these things will always show the option for two people to be the origin of all the following people.
I like the first sentence that inferring history from genetics has options for making it difficult.
Indeed it seems to be full of assumed evolutionist foundations or common descent ones.
if , as Genesis says, god created everyone with eyeballs o creation week it ALSO would likely be those eyeballs have the same dNA makeup. SO it would be wrong to insust that eyeball genetics proves a original eyeball pair in a original single type of creature.
the option for a creator means a option for creation based on a other kind of genetic relationship amongst biology.

They are arguing for a bottleneck of 2 people, and all modern H. sapiens being descended from those two people with no admixture from other populations, at least from what I have read.

I would have to agree with others that their use of parsimony is wrong. When the data can’t distinguish between a large continuous population and a bottleneck of two then you simply say that you can’t determine how big the ancestral population was. That’s the correct scientific approach. You don’t pick the smallest population that could have produced the data and call that parsimonious.

Overall, there are some clear parallels with @swamidass GAE concept. First, they are saying that a bottleneck of two is possible using the data we have at hand. Pop gen isn’t my thing, and there could be interspecies diversity which may put lower limits on population sizes in deep time, but for the purposes of this paper we could grant that over time mutations could accumulate to the point where you can’t distinguish between large ancestral populations and tiny ones. This is the same for GAE, where the de novo couple blends in with the existing population in such a way that they simply aren’t detectable with the data sets we currently have.

Where GAE and Hossjer & Gauger diverge is in the requirements for the genomes of that de novo couple. In GAE it makes sense to have a very similar genome so that the couple is genetically compatible with other contemporaneous humans. However, a de novo bottleneck of two doesn’t need to do this. What reason is there to make this couple 98% chimp, or perhaps even more like chimps since this was 500k years ago? There isn’t any requirement to do so, so why do it? Why give this couple the more than 99% of the same ERV’s as those found in chimps? Why would we see equidistance between chimp/orangutan DNA and human/orangutan DNA? I think this is the big flaw in their work.

How so? They are looking at genetic universal ancestry, not genealogical universal ancestry.

If I understand the evidence correctly, we can’t rule out a bottleneck of two 500k years ago using modern genetic diversity. That doesn’t prove that there was a bottleneck of two, but we also can’t rule it out. At least to my eyes, this is similar to your contention that we couldn’t detect a single de novo couple from 10k years ago that became part of the existing larger human population.

Oh, I see what you are saying. In that one way, there is some similarity. They are challenging a negative statement, not claiming positive evidence.

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Well, what I want to know is what kind of event caused the bottleneck and why don’t we see any evidence for such an event?But if it was more of a local thing, what kept them isolated from other populations?Seems very unlikely with what we know about hominids and how much they move(d) around. Also, the two person bottleneck would have to be a male and a female AND at the right breeding age. But yeah sure. I guess it’s “possible”. Don’t see what is parsimonious about that at all.

Note: all statements are based on my limited understanding of population genetics.

The cause could be anything for the purposes of their paper. All they are trying to do is show that it a bottleneck of two can’t be ruled out. The reason we couldn’t detect a bottleneck of two if it happened is that subsequent accumulation of mutations has covered it up.

That’s my conclusion as well.

That’s a red herring. People claimed X was ruled out by Y. They are arguing, well maybe X doesn’t rule Y out.

As for what type of event? Seems like there may be a lack of imagination here :slight_smile: .

I’m aware of what they arguing. What I’m arguing is possible != probable.

Try me. I think with what we know about how much hominids migrated around, the event that caused the bottleneck would have to be pretty widespread. So much so it should show up in the rocks. So what are we looking at? A volcanic eruption? When and where?

I’m fully aware what they are arguing. But their conclusion that it’s “possible” doesn’t entail that it’s anywhere near plausible. I’d put more money on your model being true.

Also, i thought these conclusions were reached over a year ago? So why are we focusing on it again? Seems like old news.

I have nothing to say about their population genetics work. That is out of my sweet zone. But what I am very good at is reading the rocks and fossils. Just trying to make it clear to any onlookers while this work may make it possible that we came from a pair, or maybe it doesn’t, I don’t know, there are a a lot obstacles for that to be any real possibility.

That’s just a restatement if your prior. There is no systematic way to set priors. Better to just say we don’t know.

Nope. At that point, biologos decided to ban me from their forum. This argument from Venema is pretty bad. He might benefit from getting some help from philosophers of science.

Funny. Because you said it was old news to Axe in twitter

This doesn’t seem to change anything since 2017, as far as I can tell. Maybe I missed something, but I thought the same thing about this last bit back then as I do now. Nothing seems to have changed.

Of course, maybe I missed something? Let me know if I did.

I find Dennis’ thoughts reasonable

Most his thoughts are reasonable except the ones I’ve already objected to in the past :slight_smile: