It really baffles me that non of the great minds before that period knew they existed
In: Biology
Many fossils were discovered, but they were thought to be other creatures. This included mythological monsters such as cyclops. Skulls especially were kept as trophies to display.
They found fossils before that, they just didn’t think that what they were finding was dinosaur bones. Very large bones would be considered the bones of dragons and giants. Smaller bones would just be bones, maybe bones of something we hadn’t seen before, but that’s different from knowing exactly what.
Herodotus wrote of the remains of marine animals found far inland and considered this to be evidence that the land they were found in was once underwater.
Megalosaurus is believed to be the first dinosaur ever described scientifically. British fossil hunter William Buckland found some fossils in 1819, and he eventually described them and named them in 1824.
That doesn’t mean we didn’t find them earlier, they just aren’t documented scientifically in older materials.
They did in the ancient world find fossils of things they had no way to explain. Similar to how people thought elephant skulls were evidence of cyclopes.
“Although the griffin might seem like a creature conjured from the imagination of mankind, there might actually be some truth to this creature. One theory suggests that the griffin was brought to Europe by traders travelling along the Silk Road from the Gobi Desert in Mongolia. In this desert, the fossils of a dinosaur called the Protoceratops can be found. As these bones, especially the skull, which has a bird-like beak, were exposed on the desert floor, ancient observers may have interpreted them as proof that such a hybrid creature once lived in the desert. Yet, it has been shown that stories of the griffin have been around even before the Silk Road was developed. Perhaps it was stories about the griffin that made the traders interpret the fossils of the Protoceratops as that of the legendary creature.”
Fossils and have been found for thousands of years, but were frequently chalked up to myths and legends (often because it’s very rare to find a complete skeleton). What’s more recent is the act of _exploratory_ digging, just to see what you find, as well as cooperative efforts to try and understand each others’ findings. In the just couple of hundred years, this has led to insights into what kind of creatures used to live on earth.
To provide an example, [this this what an elephant skull looks like if the tusks aren’t there](https://commons.wikimedia.org/wiki/File:African_elephant_skeleton_(11)_at_the_Royal_Veterinary_College_anatomy_museum.JPG). If people only found the skull, it wouldn’t have been obvious that it was an elephant skull even if they had seen a live elephant before. It’s believed that elephant skulls are where the mythological cyclops came from.
But even today there’s some uncertainty in what dinosaurs actually looked like. Soft tissue doesn’t preserve well and while there have been advances in that area, to where we can now find evidence of what dinosaur feathers may have looked like and possibly even what color they were, it will probably never be 100% certain. As an example, [this article](https://www.dailymail.co.uk/sciencetech/article-7754553/Nightmarish-sketches-reveal-modern-animals-look-like-drew-based-skeletons.html) has some drawings of modern animals constructed from their skeletons in the same style that many dinosaurs were just a few decades ago.
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