Our Family Tree

Humans are the only remaining descendants of a once-varied family of primates called Hominidae. In different places over the past six or seven million years, groups of early hominids adapted to their habitats and many distinct species emerged--including some that lived simultaneously. Most of these species became extinct, and only one--modern humans, Homo sapiens--ultimately survived and flourished.

Since the first hominid fossil was recognized in 1856, thousands of others representing many distinct species have been discovered. Using an array of techniques to analyze these fossils, paleoanthropologists continually develop a better understanding of the history of human evolution, represented here as a "family tree." New fossil finds and new technologies promise to refine the tree even further.

DNA Tells Us About Human Origins

© Sam Ogden / Photo Researchers, Inc.A geneticist uses a sequencing machine to work on the Human Genome Project at Whitehead Institute in Cambridge, MA.

Although it may not look impressive, the DNA in each of these tubes contains billions of bits of encoded information that can shape an entire organism. By studying the DNA from humans, and from closely related species such as chimpanzees and Neanderthals, we are piecing together the complex history of human evolution.

DNA Sample

DNA can be extracted from almost any living cell. Comparing samples from humans and other living species is helping researchers to understand what makes us uniquely human. Scientists also can isolate DNA from the fossils of some extinct species, including Neanderthals. This ancient DNA, together with DNA from living species, allows us to reconstruct key events in human evolution.

In 2001 researchers published a draft of the human genome, the DNA found inside every human. Many of the research labs involved continue to explore the human genome as well as the Neanderthal and other primate genomes with the goal of understanding human origins and improving human health and well-being.