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An asteroid killed dinosaurs in spring, which might explain why mammals survived

arstechnica.com

81–87 of 87 posts

Re: An asteroid killed dinosaurs in spring, which might explain why mammals survived

#81

Earlier quoted context omitted.

And South America and Africa were still quite close together.. the Pacific is even bigger than it is now. Literally a whole half side of the planet filled with water

> Literally a whole half side of the planet filled with water It still looks like that today! A host of images showing it: https://www.google.com/search?q=view+of+earth+pacific+ocean&...

The “Water Hemisphere” is 89% water. The “Land Hemisphere” is 85% land.

The location [0] may be a little surprising. The shared view above is deceptive due to the land at the edges.

[0] https://en.m.wikipedia.org/wiki/Land_and_water_hemispheres#/...

Re: An asteroid killed dinosaurs in spring, which might explain why mammals survived

#82
post #81

Earlier quoted context omitted.

> Literally a whole half side of the planet filled with water It still looks like that today! A host of images showing it: https://www.google.com/search?q=view+of+earth+pacific+ocean&...

The “Water Hemisphere” is 89% water. The “Land Hemisphere” is 85% land. The location [0] may be a little surprising. The shared view above is deceptive due to the land at the edges. [0] https://en.m.wikipedia.org/wiki/Land_and_water_hemispheres#/...

> The “Land Hemisphere” is 85% land.

Interesting. Not sure where you got that 85% figure though:

>> even in the land hemisphere, the water area still slightly exceeds the land area (with 53 percent water to 47 percent land)

Re: An asteroid killed dinosaurs in spring, which might explain why mammals survived

#83
post #81

Earlier quoted context omitted.

The “Water Hemisphere” is 89% water. The “Land Hemisphere” is 85% land. The location [0] may be a little surprising. The shared view above is deceptive due to the land at the edges. [0] https://en.m.wikipedia.org/wiki/Land_and_water_hemispheres#/...

> The “Land Hemisphere” is 85% land. Interesting. Not sure where you got that 85% figure though: >> even in the land hemisphere, the water area still slightly exceeds the land area (with 53 percent water to 47 percent land)

You’re right. Thanks for the clarification. 85% of Earth’s land is in the Land hemisphere.

Re: An asteroid killed dinosaurs in spring, which might explain why mammals survived

#84
post #73

Sounds convincing. But I found a flaw. Typically birds take their winter holidays in the warm continents, they don't shelter in caves. So birds would have gone extinct also. But they didn't. So maybe they did shelter in caves, such as bats do, and then later decided it would be more appropriate to spend their winter holidays at the French Riviera or Cancun and not in their caves anymore. Because the bats messed up al…

> Sounds convincing. But I found a flaw. Interesting. Are you planning to alert the journal that published the paper discussed in the article of this stunningly obvious error? It’s very frustrating that every journal doesn’t keep an HN commenter on staff so boneheaded blunders like this don’t continue to slip through.

Good idea, thanks. But before I'll consult with my local birds expert.

Re: An asteroid killed dinosaurs in spring, which might explain why mammals survived

#85

One thing that isn't talked about as much as it should be, there's a possibility that 65 million years ago during the time of the dinosaurs, the earth's atmosphere was very thick. All these Dinosaurs with their extremely long necks and bodies couldn't support their own weight if wandering around the earth today. The mass extinction event may have occurred simply because the atmosphere changed and these giant beasts u…

Can't believe the downvoting. There's several major issues with the current dinosaur theory RN. Four areas of scientific incongruities regarding these animals’ large size are 1) insufficient muscle strength, 2) insufficient bone strength, 3) unacceptably high blood pressure within the tallest dinosaurs, and 4) the paradox of pterosaurs having grossly insufficient power to fly in atmospheric conditions similar to the…

Wikipedia has entire section on Quetzalcoatlus and hypotheses around if and hoe it could fly. The consensus seems to be that it’s possible (with no mention of a denser atmosphere as a precondition or even a factor) just depending on how the musculature is modeled around its skeleton.

https://en.m.wikipedia.org/wiki/Quetzalcoatlus#Flight

Re: An asteroid killed dinosaurs in spring, which might explain why mammals survived

#86

It's incredible to me that fossils can be linked to the specific day or so of the impact.

The article says they analyzed sturgeon fossils that died in the impact, and they found they were in the growth phase typical of their reproductive season, so they don't know the year, but they know the season. The article is quite a read.

Re: An asteroid killed dinosaurs in spring, which might explain why mammals survived

#87

Earlier quoted context omitted.

Pressurized gas can act like a liquid. And at sea level, thick atmosphere would certainly be pressurized. smaller lungs aren't relevant to the issue that comes up regarding extremely large dinosaurs. Because it's not an issue of lung capacity, or oxygen supply per liter of blood. We're not talking about animals that are comparable to modern day elephants. Have you seen the size comparisons of dreadnoughtus to blue wh…

Bible scholars generally favor the idea that the expanse mentioned in Genesis - a heavy atmosphere of water vapor that is said to have given the entire earth a tropical climate - could have had a significant effect on atmospheric density, which I personally find an interesting correlation when discussing this topic. Combined with the snap frozen mammoth hypothesis, it's interesting to think that if there were a heavy…

> is it feasible that humans would live longer in higher pressures and lower UV levels

You could test this by spending the rest of your life in a diving suit: https://en.wikipedia.org/wiki/Atmospheric_diving_suit

let us know how it works out.

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