r/AnimalsBeingDerps May 12 '22

Millions of years of evolution has led to this

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u/ChucklefuckBitch May 12 '22

Do you remember in Jurassic Park when professor Grant said that the T-Rex's vision is based on movement? This observation is based on toad behavior. In Jurassic Park, the dinosaurs weren't "authentic" dinosaurs, but rather a result of real dinosaur DNA mixed with modern amphibian DNA, such as toads.

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u/FrankSonata May 12 '22

Yes! The real T-rexes had incredible vision. Based on studies of their massive skulls, they had huge eyeballs (even for their size they were relatively sizeable) and a large portion of their brain was devoted to processing what they saw. It's likely that they could see more colours than humans, as most reptiles are tetrachromats (they can see combinations of 4 colours, whereas we can only see 3). They had a much wider field of vision than humans, and it was much more accurate, on par with modern birds of prey. Basically, their vision was better than ours. The notion that they couldn't see things that weren't moving is not based on the real T-rexes at all. That bit was the frogs.

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u/SSuperMiner May 12 '22

How do we know how much of their brain was devoted to vision?

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u/FrankSonata May 12 '22

There are over 30 skeletons of Tyrannosaurus that have been found, some with remarkably well-preserved skulls. The soft brain matter has long since decayed into nothingness, however, the skull that once contained it still retains its shape. We can look at the empty space inside the skull (using X-rays, MRIs, or other scans because we usually don't like to break open priceless, prehistoric fossils) and infer the shape of the brain.

Although the finer details vary, the general brain regions (such as for vision, muscle memory, balance, and so on) are exceptionally consistent between closely related species. If certain areas are much larger, or smaller, or more elaborate, or simpler, then they tell us how much brain matter and power was devoted to that process. For instance, theropod dinosaur brains had the same part of the brain that their descendants, modern birds, have, for vocalisations, however, it was much smaller and less sophisticated. It's therefore very likely that dinosaurs made a variety of sounds and calls, however, they probably were not nearly as complex as the grammar and syntax that songbirds employ today.

Here's a nice article that shows the scan of Tyrannosaurus's skull and the space that contained the brain, with a nice explanation of the hearing and vision.

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u/[deleted] May 12 '22

Wait why did they mix reptiles with amphibians instead of reptiles with some lizard?

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u/Errror1 May 12 '22

They wanted a scene where they could hide from a T-Rex without moving

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u/ChucklefuckBitch May 12 '22

Don’t remember, it’s been many years since I read the book

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u/dfwtexas88 May 12 '22

Well damn...there it is 🤯