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Have proponents of the Chicxulub dinosaur extinction theory wildly exaggerated the effect of asteroid impact in order to validate their theory? For example,the world-wide forest fire claim doesn't stand up to examination. Fossil tree leaves contemporary with the impact & within about 2,000 miles of it have been discovered unburned,& it is impossible to start a wildfire in really damp rainforest. Also,the Deccan Traps super-volcano is likely to have made a much greater contribution to climate change. Creatures far more fragile than dinosaurs which didn't live in burrows or caves nevertheless survived the impact.

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closed as off-topic by John Rennie, Jon Custer, Ben Crowell, PM 2Ring, StephenG May 23 at 20:06

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  • $\begingroup$ But those small (mammal) survivors needed much less food per day... $\endgroup$ – Solar Mike May 23 at 17:33
  • $\begingroup$ True,but I don't see what bearing this has on the question In any case,small animals can consume as much food as large ones if they have the numbers,for example locusts & quelea. Some mammals survived in burrows & caves,others survived in the open,but I was thinking more in terms of birds & insects etc. Some large animals survived too,crocodiles & tortoises for instance. $\endgroup$ – Michael Walsby May 23 at 17:49
  • $\begingroup$ You consider crocodiles large? Compared to dinosaurs that were 50 or more tons? $\endgroup$ – Solar Mike May 23 at 17:50
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    $\begingroup$ This seems less like an actual question and more like a series of assertions. In any case, what makes you think that the global firestorm hypothesis and the Chixculub asteroid impact are one and the same thing? Evidence against the global firestorm hypothesis isn't necessarily evidence against the asteroid impact (also, most of your assertions aren't examples of evidence against the global firestorm hypothesis anyway; for example, leaves can be buried many years before the impact and still be called "contemporary"). $\endgroup$ – probably_someone May 23 at 17:57
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    $\begingroup$ I'm voting to close this question as off-topic because it isn't a question about physics $\endgroup$ – John Rennie May 23 at 18:05
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To answer your actual question:

Have proponents of the Chicxulub dinosaur extinction theory wildly exaggerated the effect of asteroid impact in order to validate their theory?

The answer is "probably not", given that the research has gradually become more and more certain about the impact's role in the extinction. If they really were exaggerating the effect, you would expect the field to eventually become less and less certain of the impact's importance over time. Roughly 20 years after the initial theory was put forward, an international team of 41 experts from various institutions and subfields evaluated the evidence gathered in those two decades to assess whether Deccan volcanism or the Chixculub impact was the trigger for the Cretaceous-Paleogene extinction event (Schulte et al, 2010, https://science.sciencemag.org/content/327/5970/1214). They concluded that the Chixculub impact was the trigger of the extinction event.

Now, to address your assertions:

For example,the world-wide forest fire claim doesn't stand up to examination. Fossil tree leaves contemporary with the impact & within about 2,000 miles of it have been discovered unburned,& it is impossible to start a wildfire in really damp rainforest.

There are several things that are problematic here:

  • The idea that the asteroid caused a "world-wide forest fire" is a separate idea from the asteroid causing the mass extinction event. Evidence against the firestorm is not evidence against the asteroid causing the mass extinction. The asteroid impact can cause a mass extinction without starting a global firestorm.
  • In paleontology, "contemporary" has a rather broad definition. Due to uncertainties in dating methods, the error bars on the ages of fossils are not uncommonly thousands of years wide. The leaves that are considered "contemporary" with the impact could have been buried centuries earlier - or centuries later (see the aforementioned paper for examples of this).
  • The asteroid impact also caused a tsunami that could quite easily bury a large amount of foliage close to the impact site.
  • It is not, in fact, impossible to start a wildfire in a damp rainforest. See, for example, this source explaining that they happen: https://rainforestpartnership.org/amazon-wildfires/. In particular, the 1997-1998 El Niño event was accompanied by fires in 13,200 square miles of Brazilian forests and rainforests.

Also,the Deccan Traps super-volcano is likely to have made a much greater contribution to climate change.

The Deccan Traps supervolcano is addressed in the paper above (Schulte et al). They find insufficient evidence that it was more important than the Chixculub impact for mass extinction. Its relevance to climate change is, again, a separate idea that doesn't really have anything to do with the rest of what you say, since climate change and mass extinctions, while related, are not the same thing.

Creatures far more fragile than dinosaurs which didn't live in burrows or caves nevertheless survived the impact.

In 2004, a team consisting of a geophysicist, an atmospheric physicist, an environmental scientist, an ornithologist, and a zoologist published an article in the Journal of the Geological Society of America which addresses how certain species may have survived the impact event (http://uahost.uantwerpen.be/funmorph/raoul/macroevolutie/robertson2004.pdf). Their survival is therefore still consistent with the asteroid impact causing a mass extinction.

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  • $\begingroup$ I have never denied that the asteroid impact played a part in dinosaur extinction. All I am saying is that there is evidence to suggest that that catastrophists have exaggerated its effect in order to validate their claim that it was the sole cause. $\endgroup$ – Michael Walsby May 24 at 10:33
  • $\begingroup$ @MichaelWalsby And you have not provided this evidence, I don't find it in my own searches, and the assertions you provided are not evidence of it, as I've explained above. Again, it seems like you came here to make a statement, not ask a question. $\endgroup$ – probably_someone May 24 at 10:38

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