English naturalist Charles Darwin is among one of the most influential figures in the history of science. Inspired by evidence that he collected during his expedition on the 'HMS Beagle' and his research regarding selective breeding, Darwin theorized that all species descended from a common ancestor. In his groundbreaking work of evolutionary biology, "On the Origin of Species," he details the scientific theory of evolution, which posits that species...

Excerpt: At the time I made the trip to Yellowstone Park with President Roosevelt in the spring of 1903, I promised some friends to write up my impressions of the President and of the Park, but I have been slow in getting around to it. The President himself, having the absolute leisure and peace of the White House, wrote his account of the trip nearly two years ago! But with the stress and strain of my life at 'Slabsides,'—administering the affairs...

Native American legends from times long ago tell of great floods that covered the earth in the Pacific Northwest. Early fur trappers describe the Willamette River as a sheet of water covering the land as far as the eye can see in the early 1800s. As American settlement of the Oregon Territory began in the 1840s, a great flood carried away many of the new businesses at the base of majestic Willamette Falls. Again and again the rivers rose, inundating...

Explore six real world habitats: forest, desert, mountains, rain forest, coral reef, and the Arctic. A dozen camouflaged animals are hidden within a large illustration of each habitat. How many will you spot?

Long before she became known as the Cactus Queen, Minerva Hamilton Hoyt found solace in the unexpected beauty of the Mojave Desert in California. She loved the jackrabbits and coyotes, the prickly cacti, and especially the weird, spiky Joshua trees. However, in the 1920s, hardly anyone else felt the same way. The desert was being thoughtlessly destroyed by anyone and everyone. Minerva knew she needed to bring attention to the problem. With the help...