# Asteroids vs Volcanos (Dinosaur extinction) **URL:** \ **Category:** Great Debates\ **Created:** [August 13, 2018, 9:53pm UTC](https://boards.straightdope.com/t/asteroids-vs-volcanos-dinosaur-extinction/819551 "2018-08-13T21:53:20Z")\ **Posts on this page:** 5\ **Page:** 2
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [August 16, 2018, 3:41pm UTC](https://boards.straightdope.com/t/asteroids-vs-volcanos-dinosaur-extinction/819551/21 "2018-08-16T15:41:53Z")
It’s Murder on the Orient Express, asteroids, volcanoes, climate, all stuck the knife in the dinosaurs. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [August 17, 2018, 12:16am UTC](https://boards.straightdope.com/t/asteroids-vs-volcanos-dinosaur-extinction/819551/22 "2018-08-17T00:16:00Z")
> [@Fotheringay-Phipps](#): > > To the contrary, I believe you are confusing two different Alvarezes. (Walter is mentioned once in passing, based on a search of the webpage.) The author mentions Walter once > [@](#): > > After Alvarez’s death, in 1988, his acolytes took up the fight—most notably his son and collaborator, Walter, and a Dutch geologist named Jan Smit, whom Keller calls a “crazy SOB.” This is bullshit, given that Luis is second author of the Science paper referenced in the article. Since Walter made the discovery, I guess that putting the Nobel Prize winner first might have been done to improve the reviews of this controversial paper. Sorry I missed Walter’s name. I’m afraid I don’t give the author of the article much credence, since it appears she never has read Walter’s book to get his side. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [August 17, 2018, 12:19am UTC](https://boards.straightdope.com/t/asteroids-vs-volcanos-dinosaur-extinction/819551/23 "2018-08-17T00:19:41Z")
> [@Martin\_Hyde](#): > > The article mentions him multiple times and very prominently, so I suspect you didn’t read very far into it. > > To me the article didn’t go deep enough into the science for me, as a lay person, to really judge which theory is correct. But it did mention that Alvarez in his lifetime was a very popular “pop scientist”, maybe akin to a Neil Tyson today or a Carl Sagan during his lifetime. Alvarez was more than happy to wield his public standing to suppress research into any alternatives to the impact hypothesis, including specifically calling out any geologists or other researchers who continued researching the volcanism theory to their employers to pressure them to reject them from tenure track positions etc. The article makes a compelling case that Alvarez using his popularity to launch a series of personal attacks on anyone who didn’t immediately embrace the impact theory to have significantly stifled the willingness of researchers to risk their careers continuing to look into alternatives or to second guess the impact theory. > > How true all that is I don’t know, but it painted Alvarez as kind of a dick, and if he really had such a stifling effect on research I think it’d make it very difficult to know which theory is correct since one of them hasn’t had the benefit of being researched as heavily. As **Fotheringay-Phipps** notes, I was talking about Walter not Luis. I’m quite aware that Luis is the one who did the marketing - he is the one I heard speak at Princeton. Walter made the discovery. Read Walter’s book - it will be clear that it is not true that he got involved only after his father’s death. ---
**Author:** ![Bookkeeper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bookkeeper/32/281_2.png) [@Bookkeeper](https://boards.straightdope.com/u/Bookkeeper)\ **Post date:** [August 27, 2018, 4:27pm UTC](https://boards.straightdope.com/t/asteroids-vs-volcanos-dinosaur-extinction/819551/24 "2018-08-27T16:27:23Z")
The Chicxulub asteroid hit at an angle that [threw blast and debris across most of North America](https://en.wikipedia.org/wiki/Chicxulub_crater#Impact_specifics), essentially wiping the continent clean of animal and plant life that wasn’t protected by a combination of burrowing or aquatic habitat and by being in the “blast shadow” of high hills or mountains. The drastic climate effects of the impact triggered extinctions of huge numbers of species in the rest of the world, most of which were already in decline due to the effects of the Deccan Traps vulcanism and other factors. The fossil record shows a decline in both population numbers and diversity of dinosaur and other large animal species towards the end of the Cretaceous period, which would have made them more vulnerable to potential extinction causes. Vulcanism was probably a major contribution to this, with the asteroid impact being the trigger event that pushed everything over the edge. (Note that there is some evidence of multiple asteroid impacts having occurred at about the same time as Chicxulub, which would have had an even greater cumulative effect.) ---
**Author:** ![etasyde](https://avatars.discourse-cdn.com/v4/letter/e/9f8e36/32.png) [@etasyde](https://boards.straightdope.com/u/etasyde)\ **Post date:** [August 27, 2018, 10:07pm UTC](https://boards.straightdope.com/t/asteroids-vs-volcanos-dinosaur-extinction/819551/25 "2018-08-27T22:07:54Z")
Pretty sure it was both (and other) causes. People always want to find _The Cause_ for things, but rarely do major events like a mass extinction have just a single cause. A lot of factors build up all at once in a crazy maelstrom of coincidence that creates a sufficiently unstable situation where _one more straw_ causes a catastrophic, cascading failure in the spine of the proverbial horse. I have seen credible arguments for environmental change, volcanic activity, even disease, and of course the geological evidence, iridium, and massive crater off the Yukatan indicating a meteor also hit. Would the meteor have wiped out as many species as it did if the volcanoes hand’t already stressed their populations? If the environment were more stable? If disease were not rampant? So while you might make a lengthy argument that the meteor or the volcanoes were the final straw, the only reason it was able to outweigh the horses’ max load so to speak is because of all the other straws. I’d say asking which one was the _final_ straw is both moot and missing the point. The real lesson, I’d think, would be to make sure you never let extinction factors stack up like that, because you never know when nature will throw the proverbial (super-massive) stone at you… which kinda doesn’t bode well for the Holocene era/extinction, what with climate change, ocean acidification/plasticisation, increased volcanism, and widespread prevalence of invasive species slowly but surely ramping up the extinction gauge :eek: [Previous page](https://boards.straightdope.com/t/asteroids-vs-volcanos-dinosaur-extinction/819551.md?page=1)