It’s Murder on the Orient Express, asteroids, volcanoes, climate, all stuck the knife in the dinosaurs.
The author mentions Walter once
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.
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.
The Chicxulub asteroid hit at an angle that threw blast and debris across most of North America, 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.)
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: