Some scientists contend that many species of dinosaur had a metabolism more like a warm-blooded mammal's than a cold-blooded reptile's.

Five hundred million different species of living creatures have appeared on Earth, nearly 99 percent of them vanishing.

As sources of electrical power, windmills now account for only about 2,500 megawatts nationwide, but production is almost expected to double by the end of the year, which would provide enough electricity for 1.3 million households.

Unlike mainstream American businesses, more than half of which fail, the failure rate for businesses in the Amish community hovers around 5 percent.

The ancient Anasazi harvested such native desert vegetation as the purple-flowered bee plant, what they now commonly call wild spinach in northern Arizona and other parts of the southwestern United States.

Rivaling the pyramids of Egypt or even the ancient cities of the Maya as an achievement, the army of terra-cotta warriors created to protect Qin Shi Huang, China's first emperor, in his afterlife is more than 2,000 years old and took 700,000 artisans more than 36 years to complete them.

During her presidency of the short-lived Woman's State Temperance Society (1852-1853), Elizabeth Cady Stanton, as she was a staunch advocate of liberalized divorce laws, scandalized many of her most ardent supporters in her suggestion that drunkenness should be made sufficient cause for divorce.

Possible long-term consequences of the "green house effect," the gradual warming of the Earth's climate, may include melting the polar ice caps and a rising sea level.

Imported into Massachusetts form Europe in 1869, the gypsy moth was used by a French scientist in an attempt at developing a strong strain of silk-producing insects, crossing gypsy moths with adult silkworms.

As Charles Darwin observed, natural selection operates whenever individuals of one genetic composition are better at reproducing than that of others.