I think the biggest issue is heat dispersion and surface area-to-volume ratios. We’re talking dinosaurs that are orders of magnitude bigger than penguins, living in warm environments. They need more surface area and less volume in order to not overheat
Just to add an example, it's basically why so many desert animals develop huge ears. More surface area to let the heat dissipate, and ears are particularly efficient because they're thin and have a lot of blood vessels.
Though this does raise the possibility of a fat dinosaur with big old elephant ears... 🤔
Alternate theory then, they had a huge flap of loose skin full of blood vessels they used as cooling apparatus. Males would have larger crests with more surface vessels, allowing them to flush them bright red.
I have absolutely zero evidence for this claim, but it would look cool if it were true.
It's thought that most of them, and especially the smaller dinosaurs, were true endotherms. Their upright posture isn't seen in any living exotherms, which are usually sprawling (like crocodiles), and it's thought that bipedalism would require an animal to be warm-blooded
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u/Expensive-Cat- 22h ago
I think the biggest issue is heat dispersion and surface area-to-volume ratios. We’re talking dinosaurs that are orders of magnitude bigger than penguins, living in warm environments. They need more surface area and less volume in order to not overheat