

How Dinosaurs Shrank and Became Birds - digital55
https://www.quantamagazine.org/20150602-dinosaurs-to-birds/

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kijin
Paedomorphosis (juvenile characteristics remaining in adults) is a really neat
mechanism for producing radically different-looking animals in a short time.

In the short span of ~30,000 years, we've managed to turn wolves into corgis
that look like puppies their entire lives. We ourselves are often said to be a
result of paedomorphosis from other primates -- now with less hair, bigger
heads, and weaker muscles.

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mirimir
Yes, indeed. For humans, it's somewhat just a change in developmental timing.
As we age, we start looking more like adult chimpanzees/bonobos.

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Radle
Simple version: The amount of Oxygen in the air decreased, giving the Dino-
birds less energy. so they became smaller.

Also air with less Oygen is lighter, another good reason for Dino-birds to
loose weight.

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cchip
On the contrary: The amount of CO₂ decreased. I see more of a correlation
between CO₂, big plants (food supplies) and animals.

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tdyen
Why is 10 million years a blip in evolutionary time when you see the massive
chamges that can happen on Islands in 100s of years?

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Synaesthesia
You can see some chang s over 100's of years. Nothing as dramatic as this. I
wouldn't call 10 million years quite a blip though. But dinosaurs were around
for almost 200 million years! Some animals have not evolved much in hundreds
of millions of years, like sharks and crocodiles.

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bsder
Yeah, it's a remarkable thing that Homo Sapiens is closer in time to
Tyrannosaurus Rex than T. Rex is in time to Stegosaurus.

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cristianpascu
Just so.

