If you are in a zoo or out in the wild, differentiating between a lion and a tiger is much less impressive than many other feats, such as walking and chewing gum or recognizing that yellow snow is not for consumption. However, when all you have is their bones, differentiating between the two becomes much more of a challenge.
According to the authors of the excellent book "The Big Cats and Their Fossil Relatives," around the turn of the century (meaning the 1800s to the 1900s), French paleontologist Marcelin Boule devised a number of criteria to differentiate the skeletons of these two animals from each other. However, these criteria aren't just "the lion has an extra vertebra," or "the tiger has a striped femur." Nothing that simple. It's more like "the tiger has a slightly more pointy fronto-nasal suture as it reaches towards the posterior end of the skull." Yeah. For the most part, not all that explicit. In the picture below (scanned from the Big Cat book mentioned above, all photo credit goes to them), you can see how subtle these differences can be.
So what are the implications for paleontologists? Ultimately, it shows us all how very little we can actually figure out about animal behavior from their bones, as well as how very similar such different creatures can be. Sure, looking at the skull of a lion or a tiger, most people would have little difficulty figuring out that they ate meat. But would looking at that slightly pointier fronto-nasal suture in the tiger really show us how much less social it is compared to the lion? Would the minute differences in the fronto-parietal suture reveal that the male lion sports a mane? Would any sort of suture be able to tell us that the lion is one of very few cats to sport a solid colored coat (like the mountain lion and the jaguarundi), while the tiger sports orange and black stripes? In the end, these minute differences in the bones remind us that we will probably never be able to learn everything there is to know about ancient and extinct species, and that there are probably many more extinct animals out there that are waiting to be discovered. It's more than likely that we already have the bones: we just need to tools to differentiate between them.
This was the birthday post of Tom Bonan! Happy birthday, Tom! If you have a birthday coming up, just email me the date at email@example.com with the date and your favorite animals, and I will do my best to get a post in! And if you like what you are reading, please feel free to follow us here or via Facebook!