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Discarded theories for dinosaur extinction

Paleontologists continue to investigate what caused all non-avian dinosaurs to die out 66 million years ago. Most agree that the impact of a large asteroid played a major role, while volcanic activity and climate and environmental changes caused might have contributed. Still, paleontologists can say for certain that some proposed explanations for the extinction of non-avian dinosaurs have proven false.

Did dinosaurs...?

Get too big to survive? No. Most of the largest dinosaurs lived millions of years before the mass extinction.
Go extinct because their eggshells got too thin? No. Although some dinosaurs did have unusually thin eggshells, many others did not. Many survivors, including birds (living dinosaurs), crocodiles and turtles, all have thin eggshells.
Die out because mammals drove them to extinction? Did mammals eat all of the dinosaurs' eggs? No. Dinosaurs coexisted with mammals for over 150 million years, so there's no reason to think that mammals would have suddenly caused dinosaurs to go extinct.
Go extinct because their babies hatched as all males or all females? No. This theory—which is based on the fact that the sex of baby alligators and crocodiles is determined by outside temperature—can't be easily tested. But it cannot explain why other animals that rely on temperature-dependent sex determination survived.

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  • aqualine ultimate style avatar for user Kathleen Marrero
    I think it was climate change, since mammals have hair or fur, and birds have feathers, they were able to survive the cold tempurature that came with the Ice age. Even if dinosaurs went extincnt before that, it might have been the gradual change, and the animals that didn't adapt, died out.
    (4 votes)
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    • piceratops ultimate style avatar for user Becky Cribdon
      Unfortunately, just the climate simply growing colder doesn't explain why many cold-blooded (so less able to cope with cold temperatures) animals survived, like crocodiles, and why many warm-blooded animals didn't, including birdlike dinosaurs, an entire branch of primitive true birds and about 90% of marsupial mammals. Climate change might well have been involved, but it was almost certainly more complicated than just one factor.
      (7 votes)
  • duskpin tree style avatar for user DragonZombZomb
    DIdn't the dinosaurs have feathers
    (5 votes)
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  • aqualine ultimate style avatar for user Aditi
    I think there would be situations like this - a asteroid fall in one of the oceans - waves - tsunami - half dinos dead - volcanic eruptions - tornados - no sun light - no photosynthesis - no food for herbivores - herbivores starved - meat eaters found dead - ate them - no herbivores - meat eaters died . The end of the dinosaurs!
    (3 votes)
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  • leafers seedling style avatar for user brylee tinsley
    Did dinosaurs get too big to survive?
    (2 votes)
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  • female robot grace style avatar for user Anna
    How can you tell the most evolved mammal like reptile(A reptile that looks like a mammal in some ways) from the first mammals?
    (1 vote)
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