At the online companion Web site of "Evolution," the seven-episode series on PBS, piece together clues to how one of our early ancestors looked as you examine images from four significant fossil finds of Australopithecus afarensis.

The quest for energy has always been a balancing act. As humans have gained greater control over their environment, they've found abundant resources - and faced numerous challenges. This article traces the history of our quest for energy.

This virtual course from Khan Academy is a series of video tutorials and practice links that follow the world's prehistory through 600 BCE.

Describes Homo habilis and Homo erectus, two early ancestors of humans. Discusses how they were discovered, their characteristics, and what we know about them, with the information clearly laid out in a chart along with some comparative...

Major Resource Kits link academic majors to career alternatives by providing information on career paths, sample job titles, and a short bibliography of Career Resource Center materials available to students in a particular major....

This site presents a pictorial timeline of technology developments.

During the first half of the nineteenth century, demand for cotton led to the expansion of plantation slavery. By 1850, enslaved people were growing cotton from South Carolina to Texas.