Human evolution, like all other species technically began billions of years ago, with the very first life forms dwelling in the boiling primordial soup on an Earth we would barely recognise. But when scientists start talking about the origins of humanity, the story begins around 7 million years before our time. At this stage, there are no humans, no chimps just a common ancestor of both swinging through the trees of a tropical rainforest that covered the entire African continent. We have never found any fossils of this mysterious creature, but scientists have already christened it Pan prior. At around this time, according to genetic evidence, the respective lineages split, going their separate ways.

Climate change probably played an important factor in causing the lineage split, at this time Antarctica was entering the final stages of its transformation into a frozen continent, with the process also occurring in the north, with a giant ice cap gradually engulfing Greenland. The freezing of the poles had an extraordinary effect on the world’s weather; lush, tropical rainforests shrank back, replaced by open savannahs covered by a strange new plant, grass, which in turn resulted in the appearance of many grazing animals familiar to us today, such as cattle, deer and antelopes etc.

It was once thought that early hominids walked, blinking and dazed out of their forest homes into the new savannahs. But recent evidence suggests that the first members of the human family tree remained tied to the forests in some capacity for millions of years after their shrinking. Currently, the oldest member of the human family tree is a creature known as Toumai (meaning ‘hope of life’ in the local Dazaga language of Chad- where it was found). The only evidence of this creature’s existence is a skull and a few teeth dated to around 7 million years, precariously close to the human/chimp split. Indeed some scientists have been bold enough to postulate that Toumai may be Pan prior, our last common ancestor with the chimps, but it’s just speculation. How can scientists deduce Toumai’s relationship to us just from us a skull? The key lies in something called the foramen magnum, a tiny hole where the spinal cord slots in. By looking at the position of this hole on a creature, scientists can determine exactly how the spine attached to the skull, and thus reveal whether the creature is a biped or a quadruped. Our foramen magnum unlike all other mammals is positioned at the base of our skull, revealing that we are indeed bipeds. Toumai’s foramen magnum is positioned more similarly to ours than other apes, making it the first biped and our earliest known hominid ancestor.

As time rolls on, these biped hominids adapt to a more open grassland landscape with clumps of forest clinging on. They diversify and speciate, but essentially they retain a close similarity with their chimp cousins, in terms of appearance, behaviour and mental complexity; the only difference being their method of locomotion.

Two of the most famous of these creatures, now known as australopithecines, are Australopithecus africanus and Australopithecus afarensis. Africanus was first discovered by Raymond Dart in 1925 in South Africa; it was a monumental moment at the time, as it was the first creature discovered that vindicated Darwin’s view that our origins lay in Africa rather than elsewhere. Dart, a charismatic scientist adamantly believed that africanus was a vicious killer that used the jaw bones of carnivores as formidable weapons. He also hinted that africanus may have been a cannibal on account of numerous decapitated hominid skulls discovered in South Africa. However, several decades later, one of Dart’s students Bob Brain revealed the truth behind the skulls. He noticed two distinctive puncture holes on top of the cranium, he found the jaw of a leopard and inserted the lower canines into the holes and found a perfect match. So instead of being vicious killers, africanus was cat food, and judging by the quantity of skulls found, a very popular prey item.

Australopithecus afarensis was made famous in the 1970s by an extraordinary discovery in East Africa by Don Johanson; he nicknamed the fossil ‘Lucy’ after the song ‘Lucy in the Sky with Diamonds’ which was playing on the radio at the time. Her remains were astonishingly complete, and seemed to reveal that by 3.2 million years ago, hominids were definitely walking around on two feet. An even more tantalising find was discovered in 1978 at Laetoli, Tanzania by Mary Leaky. A set of footprints left by a bipedal hominid had been perfectly preserved in ash that was laid down around 3 million years ago. As well as hominid footprints, the ash has also preserved footprints of rhinos, antelopes, elephants, carnivores and even records raindrops that fell at the time the ash was being laid down.

By 2.5 million years ago, australopithecines like Lucy were long gone; the climate had continued to deteriorate. The start of the ice ages was just around the corner, the African environment had continued to dry up. In response, two distinct forms of australopithecine evolved; firstly, the robusts, who come to resemble lumbering, bipedal gorillas, they adapted to eating tough vegetation such as reeds that no other ape can live on. The other form was known as the graciles, and they remained similar to their ancestors, except that their craniums, and more importantly their brains were much larger than before. No one knows for sure why brain size began to increase, was it changes in social structure or sexual selection, or a change in diet? Maybe it was a combination of factors; an interesting theory proposed by Richard Wrangham suggests that one of these gracile apes, Homo habilis, normally given the honour of being the first ‘human’ ape on account of its tool making ability, was using these new tools to pound and tenderise meat scavenged from a carcass to make it easier to chew and digest. It seems trivial, but the less time an ape has to spend chewing, the more time it can spend engaging in other tasks, thus stimulating the brain and growing smarter.

Fast forward 500,000 years and a new kind of hominid has evolved; they are first creatures to look like us, the first that we would call human, if we were to gaze upon them. They represented a monumental intellectual leap forward from the australopithecines, possessing brains 50% larger than their ancestors. Again, mystery surrounds the evolution of these more human like creatures, most scientists speculate that a total adaptation to savannah life was responsible for our body proportions and some of our curious quirks such as nakedness and sweating. These new human creatures were the first hominids to step out of Africa, populating large areas of Asia and Europe. Over hundreds of thousands of years, they evolve and adapt in accordance with their local environment. Due to their intelligence, they are also able to adapt their technology, creating better stone tools, better hunting weapons and utilising the power of fire for protection, cooking and warmth.

200,000 years ago, sees the first appearance of our own species in East Africa, at the time we shared the world with four other human species; the Neanderthals, widely distributed across Europe and Western Asia, Homo erectus, still living in Southeast Asia 2 million years after their ancestors first colonised the region, the recently discovered Denisovans, possibly an eastern cousin of the Neanderthals inhabited parts of Siberia and finally the dwarf species from the island of Flores, Homo floresiensis.

Over the next 170,000 years, our species evolved all of the behavioural faculties that make us what we are today, such as art, religion, advanced culture and trade. These factors helped to us gradually break out of Africa, and colonise the entire planet, in the process all of our human relatives go extinct, probably at our expense. Eventually our unique capacity to learn, innovate and literally change our behaviour, result in extraordinary inventions and discoveries; crucially agriculture, then civilisation. With the arrival of civilisation, humanity was now ‘free’ from the daily grind of survival; culture and technology now blossomed like never before.