Stenomylus is a funny little animal that lived a very long time ago, even before your great-great-great-great-great-great-great-great-great grandparents were born. It was kind of like a mix between a deer and a camel.
Stenomylus had a long neck and long legs, just like a giraffe, but it didn't have a big, tall body like a giraffe does. Instead, it had a smaller body that was shaped a bit like a deer's.
Stenomylus lived in a warm and dry place called North America, which is part of the same place where you live! But, Stenomylus lived there a loooong time before any people were around. It was actually around over 20 million years ago!
Stenomylus was a herbivore, which means it only ate plants. It used its long neck to bend down and reach the plants it wanted to eat. And, even though it had long legs, it was actually pretty small compared to some animals today.
Scientists love studying Stenomylus because it helps them learn more about what animals were like a long time ago. They look at its bones and fossils to learn how it moved, what it ate, and how it adapted to its environment.
So even though Stenomylus is extinct now, it still helps us learn more about the amazing animals that used to live on our planet.