Let me describe to you the Wyoming I know from 15,000 to 20,000 years ago, back when I lived here:
There are many animals that you would recognize, like jackrabbits and chipmunks. Packrats busily construct their enormous stick nests in the rock crevices. Some of their nests are still in those crevices, in your time, if you know where to look. (In fact, scientists look in those old nests for clues to the plants that are growing here now. Packrats collect debris and hide it away, then pee on it. Packrat pee is a great preservative—10,000 years later you can recognize the debris, even though it smells terrible.) In the prairies, there are herds of grazing pronghorn, Columbian mammoths, and plains bison. In the woods there are a few American mastodons, wood bison, and white-tailed deer. There are more forests now than there will be in your time. That’s because it’s colder now, and conifer trees grow at lower elevation. Prowling the edges of the forests are huge carnivores: Saber-toothed cats and American lions are waiting to ambush baby mastodons, and packs of dire wolves howl at night. American cheetahs run down the pronghorn, which is why, even to your time, antelope are among the fastest running animals in the world. Although the cheetahs are extinct, pronghorn retain the speed that saved them from being caught.
In the distance you might see me. I am a very tall camel –about seven feet at the shoulder—much bigger than your horses. Although the images show me with a hump, maybe I do not have one, as humps do not fossilize like bones do. I am eating whatever plants are available, because we camels are good opportunists. In the winter I grow a long coat and plod stoically through the blizzards. I am probably like modern camels, very good at enduring cold and heat. In the fall and winter, we form little herds of females that are defended by the larger males. If we leave the herd, we, too, risk being eaten by saber-toothed cats, dire wolves, or cheetahs. For the same reason, our babies can stand and walk behind their moms almost immediately after being born. Just recently a new predator has arrived in Wyoming, one that walks on two feet and carries a spear. He is, perhaps, the most fearsome, despite his slow pace and puny size.
Nowadays you do not see most of the animals that were in Wyoming during my time. They are extinct. Because the extinction coincided with the arrival of people, it might be that these animals were hunted to extinction. It might also be that a changing climate helped to kill them. Although a large number of large animals have disappeared since my time, there are still many survivors in Wyoming: bison, elk, two species of deer, moose, black bears, grizzlies, bighorn sheep, and grey wolves (that just were brought back!). Most of the small animals are still here as well. In Wyoming you are lucky to have all these large animals that have since disappeared from other parts of North America.