Yep, there's a huge difference between ''wiped out" and "nearly wiped out".
Yay for us!
Over 90 per cent of mammals were killed in the same impact event that caused the dinosaurs' demise after a gigantic asteroid came crashing down on earth, according to recent research published in the Journal of Evolutionary Biology. It is believed that an asteroid roughly six miles (9.6 km) across hit earth 66 million years …
Another way of reading this, then, is that the smaller animals survived. That was the smaller mammals and the smaller dinosaurs. Which happened to be in the mass range that meant, that even if their lines weren't yet flying, they would evolve flight.
Having done so, birds seem to have evolved more neuronally dense brains which means that there may be no benefit from losing flight and gaining body mass. So big mammals re-evolved (especially in the sea) but big dinosaurs didn't because being able to hop around in the treetops was just too advantageous.
But "Mass extinction that was only just survived by the smaller mammals and dinosaurs" isn't so exciting.
But, but, surely the big dinosaurs went extinct because they were too heavy for the trees? When they climbed the trees to lay their eggs in their nests, the trees fell over and broke the eggs, no?
This whole meteorite tale is just a theory.
Moa, Ostrich, Rhea, Elephant Bird, Penguins, ...
I don't see many of those 'hopping around in the treetops'.
I suspect the flightless birds evolved from flying birds, rather than being dinosaurs that couldn't climb trees. Even though they're grounded, they retain most of their bird-like adaptations, such as wings and beaks. That's why they're "flightless birds", rather than "feathered dinosaurs".
"I don't see many of those 'hopping around in the treetops'."
Well, it was a casual remark, but none of the groups you mention are anything like the size of the tyrannosaurs, or large current mammals. The largest moas ran around 200kg and evolved on an island with no large native mammals. Ostriches run up to about 150kg, small kudu size. The fact that a very few avian groups have adopted a terrestrial existence in non-niche environments and grown to sizes comparable with deer rather than, say, bison (300kg-1t), reinforces rather than detracts from my point.
Yah, well, about 12,000 years ago a similar meteor/comet strike wiped out North American megafauna and Clovis Man along with a number of civilizations on the other side of the planet in the Younger Dryas Event over which an embarrassing silence is being enforced.
< points at the other article >
There's a poster about that would tell y'all it was a lie cooked up by the scientific community to bend your brain, and that they had no clue what they were talking about. Those things are complete lies, never happened, can't happen. And he can prove it by throwing out most of the science.
< cough >
< Currently reading "Evolution: The whole story" to the ten year old for bedtime. At HIS request >
Your ten-year-old has a fine grip on reality and is to be congratulated.
I'd suggest that you move to the UK to escape the intelligent designers (or whoever they are) but you would only provoke a mindless storm over immigrants coming here to steal our welfare so, happy reading.
The Earth, as we all know, was intelligently designed.
I particularly like the fjords in Norway. They are of award-winning quality.
You need to read your child proper source material .
 Sorry it's Amazon. Your bookshop will have a dead-tree copy.
Yes, although bolide impacts get more coverage, being more exciting for those who like their science to be simple and dramatic, there's some good evidence that the dinos were dying out before the Chicxulub event occurred, coinciding with the Deccan Traps flood basalt eruption, which would have globally devastating consequences just on its own. Similarly, the earlier and larger Siberian Traps flood basalt eruption is associated with the even more severe Permian-Triassic mass extinction event, which is the only known mass extinction event where the mass extinction of insects occurred.
And just like the real killer locally with a volcano, hot and or poisonous gas and ash particulate it is also globally with massive climate change on these mega events. When people say see it was once a lot worse naturally the obvious response is yes and if we would have been around then we would probably be extinct as well.
Distance from the impact would be desirable, yes. About 3000km would be nice.
But such an impact tends to throw a lot of mass back up in ballistic trajectories that re-enter all over the planet. Think a sky full of very bright meteors. The IR alone could set fires, and thousands of heavy secondary impacts will not help any.
Then there are the other effects: earthquake-caused tsunamis, volcanic eruptions, acid rain, possible ocean poisoning from pulverized copper-heavy rock layers blasted out of the crater, and the Long Winter as dust blocks out the sun for years.
Basically the entire planet is at the same extinction risk (more or less) except for the areas within the direct-effect zone. Those areas will be nearly wiped clean of all multi-celled life, except for deeply buried nematodes and the like.
"Then there are the other effects: earthquake-caused tsunamis, volcanic eruptions, acid rain, possible ocean poisoning from pulverized copper-heavy rock layers blasted out of the crater, and the Long Winter as dust blocks out the sun for years."
Or Life After A Trump Presidency, as it's otherwise known....
Obviously not all dinosaurs were carnivores but I think it's safe to assume that most mammals must have been sitting lower on the food chain. Well, it's commonly known that predators keep other species in check, which in their turn often give birth to more siblings in order to increase their chances of survival.
Take the predator out of such an equation and you'll risk overpopulation because the hunted species can now reproduce pretty much unlimitedly, something which has happened quite a few times when people decided to remove a certain animal or place another outside of its natural habitat.
So I can't help wonder if the same could have applied here as well. With the removal of a lot of predators the mammals could much more easily reproduce and survive.
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