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varialectio t1_issb015 wrote

Bone size indicates the weight it had to support. Attachment points show what sort of musculature it had. Size and length of limbs and the angles they make with the torso indicate how it could move and how fast. Jaw and teeth give clues about diet. Then there are things like chest size and lung capacity, whether it has feathers, defensive armour which indicate a prey animal, and so on.

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Turd-In-Your-Pocket t1_issw0dg wrote

Don’t forget the little holes on bones where blood vessels attached help us know what kind of blood flow the animal needed to oxygenate its organs. Combine that with what we know of the oxygen levels in its environment and you can accurately guess the mass that was supported along with whether it was endothermic or exothermic (warm or cold blooded). We compare these to bones of existing animals, along with brain size and shape of the inside of a skull to come up with stuff like “Allosaurus ate meat and likely had the metabolism of an ostrich and the hunting and eating behaviors of a crocodile”.

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mrockracing t1_isvh0q1 wrote

Why do I feel like one day a metric ton that we thought we "knew" about the past will be radically altered or just downright proven wrong?

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triplefreshpandabear t1_isvlpf6 wrote

Probably because that's already happened a lot, but there are things we get right, science is an ongoing process, it's why scientists are very reluctant to say things definitively and instead say stuff like "research indicates" or "it's likely that" or so on to that extent. I think this makes science more trustworthy, of course media often skips that and says things like "scientists say chocolate causes cancer" or something when in actuality it'd be more like "mice who were exposed to this chemical that can also be found in small amounts in the cacao plant had higher rates of cancer than a control group that wasn't exposed to the chemical" and this sort of misrepresenting makes science seem less credible. It's why media literacy is important. A lot of what we "know" isn't things we know as fact but things that we have indications of and science acknowledges that, unfortunately popular media often ignores that.

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StrangeAsYou t1_isvlvod wrote

Of course it will be.

We now know that some dinosaurs had feathers and that's relatively new information.

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Xanderbell0120 t1_isvnuhz wrote

what indicates feathers?

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Pholidotes t1_isw1vv6 wrote

In exceptional conditions, the feathers themselves can be fossilized! China's Liaoning province is one place where this happened - it had very fine-grained sediments capable of preserving exquisite detail in fossils. For example, we know that this small theropod dinosaur (Sinosauropteryx) had a layer of fuzz similar to down feathers. And Microraptor, a smaller cousin of Velociraptor, had full-on wing feathers, plus long leg feathers and a small feathery fan on its tail.

When feathers aren't preserved in a fossil, other evidence may tip off paleontologists to the likely presence of feathers. Quill knobs, bumps on arm bones where feathers attach, have been found in several dinosaurs (including Velociraptor itself). In addition, if a certain dinosaur has no direct evidence one way or the other, but has close relatives with confirmed feathers, it can be reasonably assumed it had them too. This is akin to how extinct cats are depicted with fur because all their modern cousins have it.

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StrangeAsYou t1_isvqb46 wrote

I'm assuming they used previously unstudied fossil markers plus new examination of DNA as it relates to currently alive animals.

Advances in technology change everything.

Cars, dinosaurs, energy production, what's really alive in dirt. Everything!

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MaybeImTheNanny t1_isvyrx7 wrote

They found feather impressions first and then extrapolated. We find new things and form new theories. This particular theory is like 25 years old so not so new.

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StrangeAsYou t1_isw1yd3 wrote

25 years out of 100 thousand is pretty new.

We don't think they are mythical creatures anymore either. Dragons, griffins, hydras, unicorns.

All dinosaurs.

The real cause of the dinosaurs demise was only confirmed in 1988. There were competiting theories prior to that.

Our modern understanding is all pretty new.

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ThisVicariousLife t1_isw41rm wrote

I read an article just recently that said that scientists are starting to rethink the cataclysmic meteor theory and leaning more toward massive volcanic eruption to the scale of Mt. Vesuvius. Nat Geo Article Link

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jeveret t1_isvybia wrote

Because that’s exactly what good science does, its constantly trying to disprove/improve our current understanding. We are refining our understanding of the cosmos at an exponential rate, but we will never have all the answers, but that is not a reason to stop asking questions and looking for answers.

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Decent-Connection944 t1_iswjjsm wrote

Science is an ever evolving thing. Some answers change upon new information so what we thought was once correct is now given something different upon the presented information. So just think that it’s not wrong but there is a possibility that the theory could change and what we once thought something was is just an alternate form.

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hilburn t1_ist12nd wrote

Not to mention how they're found can give clues as to how they lived. Large groups together imply they lived in herds, smaller group with 2 adults and a number of juveniles is likely a family grouping etc

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CallMeLargeFather t1_ist2miz wrote

This seems very misleading though, usually a herd wont all die at once and fossilize right?

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hilburn t1_ist3dvy wrote

Not normally, but they can do due to particular events - mudslides, floods, volcanic eruptions etc

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xtaberry t1_ist65s7 wrote

And fossils usually form due to one of those kinds of events. The body needs to be quickly covered with sediment after death to have the best chance to become a fossil.

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EPalmighty t1_isszogf wrote

Exactly. We can also compare to modern day animals (which is kind of implied in your answer).

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simple_mech t1_istnjnm wrote

The feather and armor thing always throws me off, how would you know that from the bones?

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SexyAxolotl t1_istsqdg wrote

You wouldn't, but feaghers and scales can make imprints on the rock, similar to leaves.

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MaybeImTheNanny t1_isvyyvl wrote

Armor can fossilize depending on what body material it is. Feathers leave impressions both fossilized feather impressions and skin impressions with pimpling.

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