Final answer:
Mitochondrial DNA (mtDNA) is important for tracing the origins of humans because it follows the female line and remains relatively unchanged.
Step-by-step explanation:
Mitochondrial DNA (mtDNA) is important for tracing the origins of humans because it follows the female line and remains relatively unchanged. The mitochondria contain DNA, which is passed on from mother to offspring. This makes mtDNA helpful in tracing genealogy since mutations occur in an organized pattern, allowing researchers to determine our most recent common ancestor through matrilineal descent.