Will Clyde & Kirk Johnson 
Ancient Wyoming [PDF ebook] 

Sponsored by a grant from the National Science Foundation to the Denver Museum of Natural History. Ever wondered what the ground below you was like millions of years ago? Merging paleontology, geology, and artistry, Ancient Wyoming illustrates scenes from the distant past and provides fascinating details on the flora and fauna of the past 300 million years. The book provides a unique look at Wyoming, both as it is today and as it was throughout ancient history-at times a vast ocean, a lush rain forest, and a mountain prairie.