Holliday et al.'s Gish gallop: Summary

 

Urfa Man, Sanliurfa Museum

Previous blog posts reviewed several sections of Holliday et al. (2023), focussing on the primary impact evidence. It turns out their "comprehensive refutation" has no refutation arguments at all. Instead, it seems Holliday et al. are intent on making as many 'gotcha!' claims as possible. That is, they actively seek as many potential inconsistencies among a wide range of YDIH publications, some not even scientific papers, as they can. This is poor science. Good scientists, instead, focus on peer-reviewed research papers and whenever they encounter a potential conflict between sources first ask themselves if they have misunderstood. For example, it is often the case that a potential conflict is simply a misinterpretation. Or perhaps there have been updates since the first publication, in line with the scientific method. But, if the conflict persists and cannot be easily explained, a good scientist seeks to resolve the apparent conflict by making useful suggestions that move the science forward.

However, Holliday et al. instead use the most uncharitable interpretation of as wide a range of texts as possible and never pause to see if they might have misinterpreted them or to find potential resolutions. This is exactly what is expected for a Gish gallop. The result is that they waste everyone's time with a long-list of accusations that are easily resolved.

Furthermore, they include entire sections of non-scientific evidence that have no relevance in a scientific debate whatsoever. These are sprinkled with unjustified accusations of pseudoscience. Instead of making such accusations, Holliday et al. should check, and re-check, their own work to eliminate their own poor science. For example;

i) They frequently demand evidence for ground impacts when the YDIH is thought to be caused mainly be airbursts. Moreover, they state that cosmic impacts cannot be confirmed via microspherule evidence alone, yet this is contradicted by French and Koeberl (2010) who even list criteria for the detection of impact events using microspherule evidence alone. Microspherule evidence in the YDB at Abu Hureyra seem to fully satisfy this guidance.

ii) It is clear Daulton et al. (2010) did not sample the YDB at Arlington Canyon. Instead of a 'continuous' sequence of measurements as claimed, they took two samples from sites separated by over 7 km and 500 years. Neither sample can be expected to contain any nanodiamonds. When this error is pointed out, Scott et al. (2016/7) and Holliday et al. obfuscate. Nevertheless, Daulton et al.'s (2010) error remains. Either the coordinates for these sites, given by Scott et al. (2010), are erroneous and should be corrected, with an explanation for why such coordinates were provided in the first place, or the error should be admitted and Daulton et al. (2010) withdrawn.

iii) Meltzer et al. (2014) attempted to provide age-depth models for a series of YDB sites, claiming most of them were inconsistent with a YD impact age. However, they neglected to include any error estimates in their fitted models. Therefore, their work is scientifically meaningless and should be withdrawn. Correct analysis shows that, had they included such error estimates, it would have nullified their conclusions. The same can be said for Gill et al. (2009). Instead of admitting these errors, Holliday et al. instead attempt to defend the indefensible by arguing that such error estimates are not needed. By itself, this shows Holliday et al. fundamentally misunderstand how to analyse uncertainty in scientific data, a core competence for any scientist.

iv) Holliday et al. claim that coherent catastrophism is a 'speculative theory' without support. Instead, coherent catastrophism is inevitable. This is because we know the orbits of centaurs in the outer solar system are unstable. It is therefore inevitable that some of them will form Earth-crossing orbits at some point, thus significantly enhancing the impact risk to Earth for several millennia as they decay within the inner solar system. This follows as night follows day. Calculations of the decay of the Encke-progenitor suggest an event like the YDIH is a "reasonably probable event" within the last 20-30 thousand years or so. This is quite different to Boslough's et al.'s (2012) estimate of a chance of 1 in 10^15 for the YDIH.

v) Holliday et al. label coherent catastrophism as a "preposterous fringe idea" but seem unaware of the latest papers, published well before their "comprehensive refutation" was submitted, that show the giant comet model is the standard model for formation of the Taurid meteor stream among cometary scientists, some of whom are colleagues of Boslough. Holliday et al. even suggests the 2019 observational campaign of the Taurid resonant swarm took place as planned yielding negative results that contradict coherent catastrophism. In fact those observations never happened as intended and no papers have been published on them. Holliday et al. must know this.

vi) Sun et al. (2020), in their work on Hall's Cave, argued for a volcanic origin for the YDB impact debris. But, they neglected to publish all their data. It seems they crucially omitted data that would have lent significant support to the impact hypothesis. This needs to be explained.

vii) Jorgeson et al. (2022) don't understand the limitations of their own models. Their work suggests either i) the YDB data is inconsistent with a synchronous event,  or ii) it might be consistent and their models are inadequate. Without further evidence, no decision can be made about which possibility is correct, yet they confidently decide in favour of their models, of course. But flaws in their models were pointed out by Sweatman (2022) and these remain unanswered by Holliday et al..

viii) Holliday et al. seem to think that a layer of impact-like debris dated to within a range of 1000 years at 18 YDB sites (and counting) on 4 continents is just a coincidence. These sites are easy to find, which suggests there could be thousands of them. They have no explanation for the abundance of  microspherules, nanodiamonds and platinum together in this layer which is typically absent of evidence for volcanism. This evidence has been verified by independent research groups.

It seems the aim of Holliday et al. is to put an end to research into the Younger Dryas impact. Impact opponents publish review papers with titles such as "requiem", and "cosmic catastrophe" and "comprehensive refutation". But in each case, these works are Gish gallops, wasting everyone's time with incompetent junk.