It makes the argument, which I think is widely accepted, that dinosaurs went extinct in essentially one day, or a little longer if some survived the impact and immediate aftermath of the asteroid strike. Maybe it took a year to full extinctify all of them.
So boom. One day you've got a world full of dinosaurs munching on vegetation and each other, and then you go back a year later and you've got a barren wasteland full of corpses. The article says "the available fossil record shows that about 75 percent of known species completely disappeared, and things probably weren’t rosy for the survivors. “It’s is reasonable to suppose that the 25 percent of surviving species had near-total mortality...”. In other words, 75 percent of species were wiped out immediately, and the other 25 percent were almost wiped out.
Now, we generally have something like this happen about every 60 to 150 million years, because there have been five mass extinction events since life began forming on earth. Read more here if you're interested: https://www.nhm.ac.uk/discover/what-...sixth-one.html
For whatever reason, this is the cycle.
We had the first one, then 69 million years later we had the second.
Then we skipped a cycle and had the third one 124 million years after the second.
The fourth one was a bit ahead of schedule, happening 50 million years after the third one.
Then the fifth one (the dinosaur one) skipped a cycle and happened 135 million years after the fourth one.
Don't think about the fact that it's been 65 million years since the last one, by the way. Just put that out of your mind.
So the bottom line is that we get hammered on a cycle of about 65 million years, but sometimes we dodge the problem and get it on the next round at 130 million years.
So my question is, what would have happened if the asteroid that caused the last one 65 million years ago somehow missed us and the dinosaurs didn't get wiped out. Would we still have dinosaurs today? Or would cavemen have hunted them to extinction? Or would they have gone extinct naturally before humans came around, due to climate change or some such thing?
Disclaimer: if you believe the earth is less than 65 million years old, just move along and talk football. This thread has nothing for you. [Reply]
Originally Posted by FlaChief58:
The dinosaurs preceeded cavemen by roughly 65 million year so it's doubtful they would have had anything to do with it. If I recall correctly, the oxygen levels were much higher during the dinosaurs reign which allowed for creatures to grow extra large. If the atmosphere was changing and oxygen levels were declining, it could have been cause the extinction without the aid of an asteroid.
I think we might have seen the same thing on this. But IIRC it was actually that oxygen levels were much lower in the period leading up to the dinosaurs - due to the Permian Traps. To adapt, some animals developed the ability to absorb extra oxygen through their bones.
So when the oxygen levels went back to roughly what they are today, the animals that could get oxygen from their bones felt like superheroes, and some grew gigantic.
Originally Posted by suzzer99:
I think we might have seen the same thing on this. But IIRC it was actually that oxygen levels were much lower in the period leading up to the dinosaurs - due to the Permian Traps. To adapt, some animals developed the ability to absorb extra oxygen through their bones.
So when the oxygen levels went back to roughly what they are today, the animals that could get oxygen from their bones felt like superheroes, and some grew gigantic.
But I could have that wrong.
Yeah, it was something to that effect, but I can't remember exactly how it went [Reply]
Originally Posted by dmahurin:
I read an article just yesterday where there is speculation that the dinosaur's were on their way out already at the time of the impact so most likely, no we wouldn't. I'll see if I can find that article.
Bob Bakker was the first proponent (that I know of) of the idea that dinosaurs were already doomed when the asteroid hit. I remember him stating such many, many years ago. Bakker is memorable if you've ever seen him on a paleontology documentary. [Reply]
Cavemen wouldn't have evolved without extinction of the dinosaurs, which gave way for mammals to dominate earth.
Just saw some footage like yesterday on Reddit an attempt to hit meteor with a rocket or whatever in order to move it off course. So... looks like we'll be safe from meteors, now let's pray the aliens can save us from ourselves. [Reply]
Dinosaurs pretty much ruled the world for like 200 million years or something insane like that.
I remember reading something absurd like the Tyrannosaurus Rex lived closer to our time than the Stegosaurus' time. I think they were separated by a couple hundred million years. [Reply]
Human evolution is pretty interesting as well considering there have been a few different versions of 'humans', depending on how lax your definition of human is.
I think by most standards, you'd have to consider Neanderthals and Denisovans as human. Then you've got quite a few lesser known archaic humans as well.
The homo genus (is it genus?) has only been around for like 2 million years, which is nothing on the geological scale. At this point, every other homo group has gone extinct in just that short amount of time. Were just that unfit or are sapient just that fit to drive them all to extinction? [Reply]
Originally Posted by ThaVirus:
Human evolution is pretty interesting as well considering there have been a few different versions of 'humans', depending on how lax your definition of human is.
I think by most standards, you'd have to consider Neanderthals and Denisovans as human. Then you've got quite a few lesser known archaic humans as well.
The homo genus (is it genus?) has only been around for like 2 million years, which is nothing on the geological scale. At this point, every other homo group has gone extinct in just that short amount of time. Were just that unfit or are sapient just that fit to drive them all to extinction?
I've posted here before that it would have been interesting to be a modern human 50,000 years ago. There were five "human species" in the world at that time. [Reply]
If there’s life on other planets somewhere in the universe, it almost makes sense that one of those planets would still have dinosaurs ruling that planet because they never got wiped out by an asteroid. [Reply]
Originally Posted by Spott:
If there’s life on other planets somewhere in the universe, it almost makes sense that one of those planets would still have dinosaurs ruling that planet because they never got wiped out by an asteroid.
Cool concept.
It's so hard to believe we are the only ones in the Universe. :-) [Reply]
