Human Evolution Poster

The science

Every row is an ancestor you descend from, not a modern animal you are merely related to: the line runs from LUCA through an archaeon, a eukaryote, a chordate, a tetrapod, a synapsid, a placental mammal, an ape and a hominin to Homo sapiens. The arrows mark relatives leaving — chimpanzees at 7 million years, reptiles and birds at 310 million, bacteria beyond four billion. Each date is a divergence estimate: the point at which two surviving lineages last shared a parent.

Source. A synthesis rather than one finding. The dates follow the current consensus of fossil and molecular-clock evidence — Homo sapiens from Jebel Irhoud at around 315,000 years (Hublin et al., Nature, 2017), the human-chimpanzee divergence at 6 to 8 million years, and LUCA at roughly 4.2 billion (Moody et al., Nature Ecology & Evolution, 2024). Figures are rounded, and they move as evidence accumulates.

Why we made it. Evolution is almost always drawn as a tree, and a tree invites you to look at the branches. This is one line, because your own ancestry is one line: at every fork on the way up, exactly one path leads to you. Everything else on the page is a relative you did not become.