Talk:Toba catastrophe theory

Humans

Uh, at this time, Denisovans and Neanderthals were still around. Are they classified as humans for the purposes of this page? — Preceding unsigned comment added by 2604:3D09:657F:F030:5927:3B05:6764:D772 (talk) 10:34, 12 February 2019 (UTC)

"Human" here means species "Homo Sapiens" or anatomically modern humans. In the section on "Genetic Bottleneck Theory" the article refers to "Neanderthals and other archaic human species" as outside this definition. Perhaps it could be made clearer. Mediatech492 (talk) 15:02, 12 February 2019 (UTC)

It's becoming increasingly clear that there was significant genetic sharing between the various human species. As it is written, our text ignores this and talks of a genetic bottleneck amongst our own species when there were significant populations of other human species at that time. Neanderthals, for example, dominated Europe at that point and our lot tried and failed to displace them. We returned to Africa (some avoiding that conflict and heading off to Australia) and didn't emerge again for tens of thousands of years.

If we are casually throwing around the word "human" around, we should make it clear that we aren't referring to all humans, just our particular species. --Pete (talk) 15:27, 9 November 2021 (UTC)

Ozone

Why isn't the term ozone mentioned in this article even a single time? That doesn't seem very encyclopedic. 173.88.246.138 (talk) 19:47, 26 September 2021 (UTC)

That is a fair point but a quick search of google scholar suggests that the view that effects of ozone were important is quite recent. The article probably needs updating by an expert. Dudley Miles (talk) 20:08, 26 September 2021 (UTC)

Supervolcano Toba occurred around 74,000 years ago

There are many websites that state Supervolcano Toba occurred around 74,000 years ago, so I tweaked the article and provided a source... The Youngest Toba eruption was a Supervolcano eruption that occurred around 74,000 years ago<ref]http://haaretz.com/archaeology/2020-02-26/ty-article/.premium/no-toba-super-volcano-didnt-all-but-wipe-out-humans-74-000-years-ago/0000017f-e4ec-df2c-a1ff-fefdfc760000 </ref] 2601:582:C480:BCD0:AC73:7A8B:DDA8:A860 (talk) 11:45, 13 July 2022 (UTC)

We should not use the media, but it does reference the paper.[1] so the only question is if it is disputed. That's a 2020 paper. Doug Weller talk 12:03, 13 July 2022 (UTC)

"Toba catastrophe theory" or "... hypothesis"?

The topic of this article seems to fit the definition of a hypothesis more than that of a theory. Is the topic colloquially generally referred to as "Toba catastrophe theory", and if not, shouldn't we change the title to "Toba catastrophe hypothesis"? --Middle 8 (s)talk • privacy 18:33, 11 October 2022 (UTC); struck & changed word, 17:22, 12 October 2022 (UTC)

I think theory is the correct word. I would take it to mean an idea proposed as true, as opposed to a hypothesis being an idea not advocated but put forward for consideration. It is a theory because it has been seriously advocated. Whether it is true is a separate question. Dudley Miles (talk) 21:20, 11 October 2022 (UTC)

No, "hypothesis" and "theory" are terms of art. Theories start as hypotheses, withstand rigorous testing and gain substantial (or greater) mainstream support. [2]. Googling, I see that "Toba catastrophe theory" is the more common term, but it's really a hypothesis. [3][4] IMO, the question is whether to keep the title and note that it's a misnomer, or change it as proposed above and in the intro sentence say e.g. "(also incorrectly called Toba Catastrophe Theory)". Happy editing, --Middle 8 (s)talk • privacy 17:22, 12 October 2022 (UTC)

If you want to propose a move, you can propose it using {{subst:requested move|NewName|reason=Place here your rationale for the proposed page name change, ideally referring to applicable naming convention policies and guidelines, and providing evidence in support where appropriate. If your reasoning includes search engine results, please prioritize searches limited to reliable sources (e.g. books, news, scholarly papers) over other web results. You don't need to add your signature at the end, as this template will do so automatically.}} Dudley Miles (talk) 20:58, 12 October 2022 (UTC)

This article should be split into 3

The Pleistocene human population bottleneck relies on genetic evidence to support it. The Toba explosion is one hypothesis to explain what might have caused it. These are very distinct topics. I would suggest this page should be split into:

Toba supereruption

Pleistocene human population bottleneck

Toba catastrophe theory Bcndz5 (talk) 09:28, 5 April 2023 (UTC)

Maybe, considering that recent studies on the Toba supereruption have dramatically increased its volume estimates, and has been mentioned to be among the largest ignimbrites ever discovered. The Space Enthusiast (talk) 15:13, 5 April 2023 (UTC)

That bottleneck section is outdated and contains some misunderstandings. To list a few:

1) The original bottleneck hypothesis, which Gibbons, Ambrose and Rampino relied on to make connection with Toba, was proposed by Harpending in [5]. It simply stated that population grew from 1k-10k individuals about 50ka. It provided no evidence if population was greater than 1-10k before 50ka, no evidence of population contraction. In fact, Harpending himself argued that it was not greater for the past 2Myr [6]. In this model, human population was never reduced but was at a constant, low level from 2Myr to 50ka, resembling a bottle (50ka to present) with long neck (2Ma to 50ka).

2) Toba-bottleneck theory proposed that YTT, Greenland Stadial 20 and MIS-4 together (lasted 15-20kyr) reduced human population. The theory author acknowledged that Toba alone was not sufficient to leave imprint on genetics [7]. MIS-4 probably did the most work.

3) The current genetic studies point to a severe bottleneck in non-Africans and a mild bottleneck in Africans both at 50-100ka [8][9][10][11][12][13]. The severe bottleneck (10-fold reduction) in non-Africans is attributed to Out-of-Africa founder effect. The mild bottleneck (2-fold reduction, remaining effective population size between 10,000-20,000) in Africans maybe related to deteriorating climate at the onset of MIS-4, or founder effects inside Africa[14][15].

I agree with you that these are two very distinct topics. I think the entire article should be changed to reflect the actual hypothesis that Toba-Stadial20-MIS4 caused the population crash. Aleral Wei (talk) 18:59, 22 June 2023 (UTC)

I would agree. The eruption and the bottleneck at the very least should to be split off.

Kingsmasher678 (talk) 16:35, 22 April 2024 (UTC)

Should it be Level 9 now?

Supposedly the eruption produced 13,200km ^3 of cubic material which Volcanic Hub did talk about in his video. But I'm curuious to know if any of you think if it should be changed to level 9 because of the estimation being changed and underestimated Colin777724 (talk) 21:16, 27 June 2023 (UTC)

Revised down to 5600-km³ https://doi.org/10.1016/j.jvolgeores.2023.107879 Aleral Wei (talk) 05:58, 1 September 2023 (UTC)