Compare hominins side by side

How to read a hominin comparison

Putting two species side by side is the fastest way to feel the difference between them — and the fastest way to draw the wrong conclusion. A bar chart makes every number look equally solid. In palaeoanthropology they almost never are. Some of the figures above rest on hundreds of specimens; others rest on one damaged skull and a lot of careful argument.

Three things are worth knowing before you trust any single comparison.

Height is an average of very few individuals

For Homo sapiens we have billions of living people to measure. For Sahelanthropus tchadensis we have a single distorted cranium and no postcranial skeleton at all, which is why its height is listed as unknown rather than estimated. Most early hominins sit somewhere between those extremes.

Early hominins were also strongly sexually dimorphic — males were substantially bigger than females. Australopithecus afarensis is the clearest case: Lucy stood about 105 cm, while male individuals from the same species reached roughly 150 cm. A single "average height" hides a difference of nearly half a metre. When you compare Lucy to a modern human, you are comparing one small female to a species-wide average, and the gap looks larger than it really was.

A bigger brain is not automatically a smarter one

This is the comparison readers misread most often. Neanderthal braincases run from about 1,200 to 1,750 cc, and the average sits at or slightly above the modern human average of roughly 1,350 cc. Neanderthals did not therefore out-think us.

Absolute brain volume scales with body mass, and Neanderthals were heavier, stockier and more muscular than most living humans, with a larger visual cortex to run bigger eyes adapted to high-latitude light. Researchers usually control for this with the encephalization quotient (EQ) — brain size relative to what an animal of that body mass would be expected to have. Brain shape matters too: modern human braincases are globular, with expanded parietal and cerebellar regions, while Neanderthal braincases are long and low. Two brains can be the same size and organised quite differently.

Homo floresiensis makes the opposite point. Its brain was around 426 cc — smaller than a chimpanzee's — yet the Liang Bua deposits contain stone tools and evidence of butchery. Raw volume is a weak predictor of behaviour on its own.

Why so many of the timeline bars overlap

The most surprising panel on this page is usually the timeline. Human evolution is often pictured as a relay race in which one species hands off to the next, but the bars overlap constantly, because for almost all of the last four million years there was more than one kind of hominin alive at once.

Around 1.8 million years ago in East Africa, Homo habilis, early Homo erectus and Paranthropus boisei were all living in the same landscapes. Far more recently — around 50,000 years ago — the planet still held Homo sapiens, Neanderthals, Denisovans, Homo floresiensis on Flores and Homo luzonensis in the Philippines. A world with only one human species is the strange, recent exception, not the rule.

Overlapping in time does not guarantee overlapping in place. Use the fossil-sites map to check whether two species were ever plausibly in the same region before assuming they met.

Where these numbers come from

Height and brain volume here are representative adult figures compiled from the Smithsonian Human Origins programme, the Natural History Museum in London, the Australian Museum and the primary descriptions of individual specimens. Where a species is known from very few individuals, the range is deliberately wide.

Denisovans are the hardest case on the list. They are defined largely by their genome rather than their skeleton — a finger bone and teeth from Denisova Cave, plus the Xiahe mandible from the Tibetan Plateau. There is no reliable Denisovan stature estimate, so the height panel shows them as unknown rather than guessing.

The reconstruction portraits are interpretive illustrations, not photographs or forensic reconstructions of specific individuals. Skin tone, hair and soft tissue are informed guesses; only the underlying skeletal proportions are constrained by fossils.