The machines read each piece and, through computational analysis, we reconstruct genomes. These genomes can be compared to known reference genomes to identify species, ancestry, or even ancient pathogens.
Reconstructing Life from Molecules
From a few milligrams of bone powder, we can reconstruct entire histories. Ancient DNA helps us map human migrations, trace family relationships, and identify interactions between people and their environments. It connects biology to archaeology, showing that every artifact or burial represents not only a cultural moment but also a genetic snapshot of life in the past.
One way we apply these same biological principles is by studying Y-chromosome inheritance. The Y chromosome is passed almost unchanged from father to son. In ancient DNA, that means we can sometimes trace paternal lineages through time, connecting individuals who lived generations apart. For example, if two males from the same archaeological site share the same Y-chromosome haplogroup, it suggests they may belong to the same extended paternal family or community. By comparing Y-chromosome and mitochondrial DNA (which is inherited through the maternal line), we can reconstruct how populations were organized, how people moved, and whether they practiced patrilocal or matrilocal residence patterns. The same inheritance rules you learn in Punnett squares help us piece together real ancient family trees.
Ancient DNA has also helped scientists understand how lactase persistence, the ability to digest milk as an adult, spread through Europe. You may have learned in class that the ability to digest lactose depends on specific regulatory variants near the LCT gene.
