Glossary

The terms

Haplogroup

A branch on the human family tree, defined by a set of mutations everyone on that branch inherited from one common ancestor. It traces deep ancestry over thousands of years — not recent family history.

Y-DNA

DNA on the Y chromosome, passed father to son essentially unchanged. It traces one line: your father, his father, his father. On this site: E-M81, E-PF2546

mtDNA

Mitochondrial DNA, passed from a mother to all her children, but onward only by her daughters. It traces the equivalent single line through mothers. On this site: H1-T16189C!

Subclade

A branch of a branch. E-PF2546 is a subclade of E-M81, which is itself a subclade of E-M96. The deeper the subclade, the more specific and the more recent.

TMRCA

Time to Most Recent Common Ancestor — an estimate of when everyone carrying a lineage last shared one ancestor. Always an estimate with a range, never a measurement.

Coalescence

The point, going backwards in time, where the branches of a lineage converge on a single ancestor. A coalescence date and a TMRCA are the same idea from opposite directions.

Molecular clock

The method behind those dates: count the mutations separating two sequences, divide by an estimated mutation rate. Change the assumed rate and every date shifts — which is why published ranges are wide.

Ancient DNA (aDNA)

DNA recovered from archaeological remains — bone, teeth, sediment. It tests migration hypotheses directly instead of inferring the past from living people, but it survives poorly in warm climates, which is why North Africa's record is thin.

Admixture

Two previously separate populations mixing. Asymmetrical admixture is when the sexes contribute unequally — the pattern behind an African paternal line sitting beside a European maternal one.

Patrilocality

A social pattern where men stay in their birthplace and women move to their husband's community. Over generations it pins paternal lineages geographically while maternal ones travel.

Star-like expansion

A pattern where many branches radiate from one point with little depth between them — the signature of a small founder group that grew fast. E-M81 shows it.

Control region

A non-coding stretch of mitochondrial DNA that mutates relatively quickly, making it useful for defining recent maternal branches. The T16189C marker sits here.