How To Clearly Tell Difference in WY State Mammal Bison & Buffalo
Don't be confused, when in Yellowstone or most places in the North America, you're not seeing Buffalo you're seeing the American Bison. There is quite the difference and if you'll follow along, I will explain it.
When the first explorers made their way west they came in contact with these massive beasts, that roamed the plains in the millions and started hunting until they thinned the herds greatly. Bison were hunted so often, they were almost eliminated in the late 1800's. In the early 1900's the US Army brought 21 Bison into Yellowstone and protected them and eventually were able to bring back to a comfortable number like we have now in the park.
Even back as far as those early day's Bison have been (by some measures) incorrectly called Buffalo. Other than being both big, having horns and being extreme distant cousins in the Bovidae family, the American Bison isn't even closely related to the Buffalo.
One difference you can see immediately between Bison and Buffalo is the Bison's large hump on it's back. This may shock you, but according to NPS.GOV the Bison's hump is made up of muscles and long vertebrae so they can use their head as a snow plow to get to plants to eat during the winter. That comes in really handy during the Wyoming winters.
Yep! The American Bison is a natural born snow remover!
The Smithsonian's National Zoo & Conservation Biology Institute points out that "True Buffalo" are actually native to Africa and Asia (Cape Buffalo and Water Buffalo), so living in the warmer climates, they wouldn't need the type of thick coat of fur that the Bison of North America need during the winter months. You'll also notice that the Bison has a nice "mountain man" like beard to go along with that big winter coat. Of course the hot summers and to cool down the bison will shed the thick warmth for a lighter/cooler summer coat.
The next difference will come when you're looking at the horns of the Buffalo and Bison. African Water Buffalo have long, large curved horns, the Cape Buffalo has horns that dip down and look like a mustache coming out of the top of their head and the Bison horns are sharp and shorter than the others.
Historians believe the reason many call the bison, buffalo is a simple play on words. Early explorers called bison by many names and that the French word for beef "boeuf" is where the name originated. Others believe the Bison's coat resemble a "buff" coat (a popular coat worn in those times) and that's how they started to be called "Buffalo". Since that was EARLY in our countries history, the origins of why they were called Buffalo are a little sketchy, but what we do know is that here in North America...they're Bison!
I'm fairly certain that you're not going to get in trouble for calling a bison, buffalo...BUT, just wanted you to be informed when you were in a deep conversation about western U.S. history and so you can school the "Tourons" on your next visit to Yellowstone.
Here are a couple videos to help you out too. One is from that show the LiveScienceVideos on YouTube that breaks down the difference with video evidence. The other is from the National Park Service Yellowstone showing about the Bison in the park. Enjoy!