Ancestor

sew your family tree back, a generation a row.

a sampler where each row is a village of 32; your tree doubles every row, the village does not, until a stranger's tree and yours are the same people

Everyone has 2 parents, 4 grandparents, 8 great-grandparents: 2 to the power n, n generations back.

Concepts: exponential-growth, history.

An interactive you play with one thumb, on Wundr.