Smilodon
Discovered: Technically The 1830s
Location: Extinct (Lived In North & South America)
The Smilodon might be known best by its incorrect nickname, the saber-toothed tiger. When fossils were discovered starting in the 1830s, it was easy to see why so many could assume it was a tiger. It appeared to be large just like most of the Panthera species we see today. The species also had two large fangs that actually stuck out of its mouth. These were likely not even needed, as the smilodon had large razor-sharp teeth beyond the fangs. The similarities made it hard to assume it was not some sort of prehistoric cat. However, as more evidence came through, scientists found it was more robust in its body than any cat during or before its time.
That made the scientific community research into the species more. This led to the groundbreaking discovery that this was no cat but rather, it was a carnivorous marsupial. The discovery was easier to make since we had so much information about other carnivorous marsupials still living today, which it seemed to have more in common with. All Smilodon died out around 10,000 years ago, the same time most other megafauna died off. The reasoning was not just climate-related but, rather, due to its reliance on large animals for food. As those animals died off, the smilodon ran out of viable food sources and slowly met its demise.