In this 16-minute video presentation, Scott R. Woodward, executive director of Sorenson Molecular Genealogy Foundation, explains what DNA is, what it can teach us, what its weaknesses are and how it can be used to understand and track relationships between individuals and groups.

Woodward discusses the difference between the portions of DNA that are used to track groups and used to identify specific individuals. He explains the difference between using mitochondrial DNA, which tracks only the female line, and Y-Chromosome DNA, which tracks the male line.

Woodward tells how all of us have a real physical connection with other people on earth.