Early Human Timelines
When Did Humans Evolve?
With more than 7 billion members spread across the entire globe, the species Homo sapiens is one of the most successful species on the planet. Humans branched from the chimps around 6 million years ago and are now the only surviving member of an extensive human family tree. It was not always like this; until relatively recently Homo sapiens was one of several human species that roamed the Earth. Fossil evidence suggests that there are more than 20 hominids that make up the human family tree.
If we know that we are one of many human species this raises the question: What makes a human? We can recognise the earliest human remains due to several distinguishing features:
- Large brain
- Lightweight, bipedal skeleton
- Skull with short base and high braincase
- Small brow ridge
- Chin on lower jaw
Whilst this allows us to distinguish the onset of anatomically modern humans, it requires more detailed palaeontology to distinguish the two greatest features of modern humans - culture and language.
Human Evolution - The Homo Genus
2.5 - 1.4 MYA
1.7 - 1.5 MYA
1.9M - 143,000 years ago
700,000-200,000 years ago
Man from the Neander Valley
200,000-28,000 years ago
95,000-17,000 years ago
195,000 years ago - present
When Did Humans Start Walking Upright? Australophicines
The evolution of an upright posture is one of the two key dividing lines between humans and apes. Bipedalism has many advantages:
- Hands are left free to hold tools and reach fruit hanging from the ground
- Predators can be spotted from much further away
- Exposure to the sun is reduced
- Boosts motility - particularly over long distances
Australopithecines were the first early humans to start walking upright. This early species of hominid first evolved around 4 million years ago and lived on the African Savannah - possibly due to climate change forcing them out of the forests in the search for food and water. With a brain size only 400-500 cubic centimetres, Australopithecines were still quite ape-like in appearance, and also showed a high level of sexual dimorphism - males could be twice the size of females. This was the first step on the road to humanity.
When Did Humans First Start Using Tools? Homo habilis
Homo habilis was the first human ancestor to habitually use tools - hence its name, 'Handy Man.' Equipped with a much larger brain than Australopithecines (around 600cm3), 'Handy Man' used tools to break bones and extract the nutrient-rich marrow. The tools were made of sharp stone flakes (Oldowan tools). Homo habilis crucially also had weakened jaw muscles - a mutation though to clear the way for rapid brain evolution. Other primates have strong jaw muscles that exert force across the entire skull - constraining its potential growth. Large brains need huge amounts of energy - as brain size increases we see cultural changes such as transition to eating meat, seafood entering the diet and the invention of cooking
The Evolution of ManClick thumbnail to view full-size
When Did Humans Leave Africa? Homo erectus
Humanity is truly a global species - several times in our history we have made the voyage out of Africa. Despite having brains sophisticated enough to fashion tools (albeit not tools of a preconceived design) Homo habilis never left Africa; this was left to Homo ergaster/erectus (the species is called ergaster in Africa and erectus by the time it reaches Asia). It is suspected that the species larger size coupled with overcrowding or climate changes first triggered humanity's egress from the cradle of life. As the most human-like ancestor in the lineage (long legs, shorter arms), Homo erectus was also very well adapted to upright walking - a much more efficient mode of movement than those used by other primates.
When Did Homo sapiens First Appear?
Anatomically modern Homo sapiens first evolved around 200,000 years ago. By this time, cranial capacity had increased to around 1300 cm3, requiring anatomical changes to accommodate this such as a high and wide braincase. Mutations in the gene FOXP2 (possible arising as early as Homo heidelbergensis 600,000 years ago) had allowed for the development of speech - one of the key developments that allowed humanity to take over the world. By talking, knowledge could be shared far more efficiently, allowing for an increased rate of technological, cultural and spiritual advancement.
For much of our 200,000 year history we have shared the planet with a number of other species of humans. Homo neanderthalensis are perhaps the best known of these colleagues. Like Homo sapiens, Neanderthals had culture, controlled fire, designed and made sophisticated stone tools, wore clothes and created jewellery. They were also larger than modern humans and had a larger brain...so where did they go?
It is highly likely that the rise of modern humanity heralded the demise of the Neanderthal...a depressingly common theme in our history. Disease, competition for food, or outright warfare have all been cited as possible causes for Neanderthal extinction. Coupled with climate change and a reduced ability to adapt all put paid to the most well known of our human relatives.
Where Next? Human Evolution
- Early beginnings of modern humans | Natural History Museum
Find out the features that characterise our own species, Homo sapiens, and get to know some of our most significant early relatives.
- Human Family Tree
A flash-driven site looking in detail at all aspects of the human family tree. A great site from the Smithsonian Institute and highly recommended. Comes complete with reconstructions of each species.
- BBC - The Evolution of Man
From tree dwelling ape to civilisation! Videos, reconstructions and background from our own pre-history