Prehistoric World

150,000

Homo sapiens
Part 1 of 6

Fully modern Homo sapiens ('wise man') may not have appeared in its current form until as late as 80-60,000 years ago.

Prior to this, the first appearance of archaic man around 200,000 years ago had followed about 100,000 years of gradual transition from the features of its possible predecessor, Homo Heidelbergensis (possibly now replaced by Homo bodoensis), to those of Homo sapiens. Perhaps this is the best example of evolution at work - not a sudden process (although in evolutionary terms 100,000 years is extremely brief) but a gradual transition across several hundred generations. A small development in the jaw here, a minor cranial enlargement there, a little less body hair than with the father... Even today, such changes would not seem especially remarkable on a case-by-case basis. It would be hard to see evolution happening at all.

Homo sapiens became established in Africa after transitioning from - it has generally been assumed - heidelbergensis and testing out various advancements in the form of Homo rhodesiensis and Homo sapiens idaltu (and quite possibly others which remain to be discovered).

Homo sapiens had a characteristic look: their faces were (and of course still are) small and tucked under a high, domed braincase. They had small eyebrow ridges and their lower jaw ended in a prominent chin. On average, their bodies were less robust and less muscular than those of earlier hominids.

The appearance of modern humans coincided with the appearance of highly crafted tools, efficient food-gathering strategies and a complex social organisation, although precisely when this occurred is still very much open to debate.

New dating in 2017 of fossils found in Israel indicated that some Homo sapiens groups had managed to make the crossing out of Africa during one of the periodic phases which allowed such access. They were present there by about 185,000 years ago (with a possible window of 10,000 years in either direction). The fragments of jaw discovered there showed very clear modern human characteristics. This was not a major 'Out of Africa' migration, though. Just one in a series of temporary expansions by small groups into the Levant before climate or Neanderthal competition either forced them back into Africa or killed off these migrant bands.

146,000

Homo denisovan (Homo longi / Homo daliensis)
Part 3 of 4

The rediscovery in China in 2018 of a huge fossilised skull which had been hidden in 1933 sparked some discussion about its origins. Chinese researchers were quick to give it a new species name: Homo longi or 'Dragon man'.

The skull is 23cm long and more than 15cm wide. It is substantially larger than a modern human skull and has ample room, at 1,420ml, for a modern human brain. Beneath the thick brow ridge, the face has large square eye sockets, but is delicate despite its size.

In general it is closer to modern humans than it is to Neanderthals, but may be similar to a 1978 discovery in China's Dali county, earning it the alternative name of Homo Daliensis.

It clearly forms a separate lineage from either humans or Neanderthals though, with the possibility (especially given the relative vicinity of the Altai Mountains) that it forms a branch of Denisovan.

That potential link was strengthened by fresh research which was published in 2024. Denisovans appear to have supplied an interbreeding gene to modern Tibetans which makes it easier for them to survive in their high-plateau climate.

100,000

Homo sapiens (Nesher Ramla)
Part 2 of 6

In search of new food supplies, Homo sapiens began to cross from Africa into the Near East. They may not have been the first of their kind to make the journey, however, as the Nesher Ramla Homo group already seem to have been well established by about this time (see the Mousterian culture link, right for more).

By this Late Pleistocene period, its numbers appear to have been dramatically reduced by a lack of food stocks, perhaps to as low as two thousand individuals in the main groups (according to genetic research in the early 2010s), which meant that for a while Homo sapiens was perilously close to extinction. Other, smaller groups seem to have remained in Africa.

By a strange twist of fate, the harsh conditions which caused this near extinction may also have allowed the cultural explosion which gave rise to human behaviour as we know it today. By 2004 Professor David Goldstein, a molecular biologist at UCL in London, had announced evidence uncovered to back up the idea of a very ancient population bottleneck. A bottleneck is an event which reduces the genetic difference, or diversity, in a population of animals. One way this can occur is through a catastrophe which wipes out a large proportion of a population.

When the genes of modern people from all over the world are compared, they are remarkably similar, suggesting that the ancestors of all living people expanded from a small population which survived a bottleneck. The genetic data suggested that the bottleneck was not a recent occurrence, putting the likely date for this event at just before 100,000 years ago. This was at the very dawn of man's migration out of Africa, although some opinion places that event later, so Africa was certainly the location of the bottleneck event.

It's not known what caused this bottleneck. But a plausible candidate is emerging. By measuring the ratios of different oxygen isotopes in ice cores, scientists can reconstruct climatic changes over time. Oxygen isotope data suggests that between 190,000 and 130,000 years ago - a period known as 'oxygen isotope stage 06' - Africa was drained of moisture and became a parched wasteland, with little to sustain populations of modern humans. The scale of climatic change seen at this time could be responsible for what has been seen in the genetic data.

95,000

Homo floresiensis

A tiny species of human existed in Indonesia at the same time as Homo sapiens was first migrating out of Africa.

Homo floresiensis was a one metre-tall species which lived on the island of Flores (near Java). It had long arms and a skull the size of a large grapefruit, and it shared its habitat with a golden retriever-sized rat, giant tortoises, and huge lizards - including Komodo dragons - and a pony-sized dwarf elephant called stegodon which floresiensis probably hunted.

Floresiensis evolved from Homo erectus, whose remains have been discovered on the Indonesian island of Java and may also have existed to the north of Flores Island, although no finds have so far been discovered. Homo erectus may have arrived on Flores about one million years ago, evolving its tiny physique in the isolation provided by the island in response to the local scarcity of resources (later influxes of Homo sapiens appear to have evolved in the same way to produce pygmies).

Homo sapiens reached the area by 50,000 years ago, by which time this earlier hominid may already have died out. The finds at Liang Bua were initially dated to a point just before 12,000 years ago, when a volcanic eruption snuffed out much of Flores' unique wildlife, but subsequent analysis has pushed the finds back to between 50,000 and 60,000 years ago.

The initial population on the island of Flores would have been full-sized Homo erectus specimens, but the limited resources available on the island meant that succeeding generations were born which were shorter and smaller, producing Hobbit-sized humans within 300,000 years

The initial finds also suggested an arrival date on the island for floresiensis of around 95,000 years ago. But with more information now available this date has also been pushed back, to around 700,000 years ago.

The latest discovery, from Mata Menge in 2015, was of fossils which date to this period. They indicated that the normal-sized erectus individuals who first set foot on Flores shrank 'rapidly' to become Hobbit-sized. The remains are of at least one adult and two children, who are all just as small as their descendents.

Stone tools at the same site are even older, at around one million years. It seems likely that a small erectus population found itself trapped on the island and made the best of the situation. Homo erectus was too primitive to be able to craft boats, so they may either have been carried there accidentally by storm weather or they found a temporary land bridge which has left no trace in today's archaeological record. Once stuck on the island, they adapted remarkably quickly to the lessened resources. In just 300,000 years they were fully Hobbit-sized, a remarkably quick transformation in evolutionary terms.

A branch which is probably related to floresiensis, Homo luzonensis, has also been found in South-East Asia.

90-70,000

Homo sapiens
Part 3 of 6

Having migrated out of Africa and into the Near East over the course of several thousand years, some groups of Homo sapiens followed the coastline, heading eastwards into Persia and South East Asia.

Other Homo sapiens groups settled along the Fertile Crescent and in the south-eastern corner of Anatolia. They lived alongside tribes of Homo neanderthalis, and there was a considerable overlap in the competition for resources between the two species which lasted for at least 30,000 years (as proven by the discovery of Kebara, a Neanderthal fossil found in Israel and dated to 60,000 years ago). This span was nearly five times longer than when sapiens later reached Europe. The considerably smaller numbers of sapiens at this time, as they moved into a land dominated by neanderthalis probably goes a long way to explaining this.

However, one significant drawback for Neanderthals was the fact that their physique forced them to maintain a high calorific intake. They were forced to hunt for food containing twice as much energy as that required by Homo sapiens. Once they found themselves in direct competition with increasing numbers of Homo sapiens, their hunting successes would have been harmed, perhaps significantly. This would certainly have had a detrimental effect on their existence.

Did this process of being out-competed by sapiens cause Neanderthal tribes problems? Not immediately, but over time they would have suffered. By the period between about 60,000 to 50,000 years ago, some of them were interbreeding to a limited extent with local sapiens populations, enough to leave a trace DNA of up to two per cent in today's Europeans and Asians.

70,000

Homo sapiens
Part 4 of 6

There may have been other bottlenecks which contributed to the small amount of genetic diversity seen in modern humans, but one around this time certainly had a noticeable effect.

Professor Stanley Ambrose of the University of Illinois at Urbana-Champaign believes that the eruption of the volcano Mount Toba in Sumatra (dated to 74,000 years ago) was responsible for a volcanic winter which caused an instant ice age. The large amount of sulphur thrown up into the atmosphere by the eruption reflected sunlight away, causing temperatures around the world to plummet. Temperatures in Africa may have fallen by as much as nine degrees Celsius, creating a freeze which lasted 1,400 years.

While it was unrelentingly cold for a long time, a temperature change of this magnitude would almost certainly have caused another terrible drought. Lakes would have dried up, and the soil would have turned to sand. Every year of drought would have been geometrically worse than the year before.

Ambrose believes it was no coincidence that, around this time, modern humans in Africa were undergoing drastic changes in the ways in which they organised their societies. The harsh climatic conditions which accompanied the volcanic winter may have placed pressure on humans to cooperate with each other. Small foraging groups became larger societies. Ambrose calls this the 'troop-to-tribe transition'.

In India, groups of Homo sapiens had been in direct competition with Homo erectus since the former had arrived there. Homo erectus was a fast, agile hunter which used stone knives to kill and butcher its prey, and was not averse to eating the odd Homo sapiens which it came across. However, sapiens was able to out-think its rival, and was armed with stone-tipped spears which erectus never developed. After the Toba freeze, only Homo sapiens leaves any traces of existence in India. There are none from erectus, suggesting that they failed to survive there and were never to return - a disastrous outcome for them.

However, there seem to have been one or two regions which were less noticeably affected by the eruption. Excavations in South Africa (in 2017) suggested that settlements there not only endured the cataclysm, but may have 'thrived' in its wake. Shards of volcanic glass were found in the sediment at two sites on the south coast of South Africa. These have been scientifically linked to Mount Toba. After the Toba eruption, the intensity of population increased in these sites. People were in bigger groups at the sites, or were staying there for longer periods. The clear inference is that groups travelled southwards to escape the worst of the volcanic winter. When it eased, they would have been able to start migrating northwards again, ready to burst into the Near East and further afield.

But was there a cause behind such a massive volcanic eruption? Probably not, other than the usual tectonic activity seen along the Pacific Ocean's eastern rim. However, it's a remarkable coincidence that a 2015 discovery, published in Astrophysical Journal Letters, showed that an 'alien star' passed through the outer reaches of the solar system around this time.

The star was a red dwarf known as Scholz's star, and it cruised through the outer reaches of the system, carving a path through the Outer Oort Cloud, beyond Pluto's orbit. It was accompanied on its travels by a brown dwarf (essentially a failed star which lacked the necessary mass to trigger fusion at its core). It came five times closer to our own sun than our normally-nearest stellar neighbour, Proxima Centauri.

The effect of a passing star on the Oort Cloud is a function of the star's mass, speed and proximity. The worst case scenario for stirring up comets would be a slow-moving, massive star which came close to our sun like this. If the star itself didn't have any effect on Earth's volcanic activity, could a particularly large comet thrown out by the disturbance?

70,000

In 2011 a DNA sample from a lock of hair demonstrated that indigenous aboriginal Australians were the first to separate from other modern humans, around 70,000 years ago. They entered Australia by 50,000 years ago, giving them a longer claim to the land in which they now live than any other population known.

A number of them may also have ended up in South America after their ocean-going vessel was blown off course (see sidebar link).

Belonging to the Australoid group, they are more closely related to Africans than they are Asians or Europeans. They were probably part of the wave of humans who entered into India from the Near East, mostly following the coastline as they headed into South East Asia, although some groups probably followed the Ganges to cut across the sub-continent.

Given their relatively early arrival in Australia, it seems likely the aborigines were amongst the first modern humans to leave India, too early after the migration out of Africa for the changes which resulted in modern Asians to have appeared in them.

67,000

Homo luzonensis

The big news of 2019 was of the discovery of another new human species, this time from Callao Cave to the north of Luzon, the largest island in the Philippines.

The new find was labelled Homo luzonensis, with dating placing it between 67,000-50,000 years ago. Its physical features were discovered to be a mixture of those found in very ancient human ancestors and in more recent people. The find shows that human evolution in the region has a complicated story, with at least three human species already established in the region (erectus, floresiensis, and luzonensis) when modern humans finally arrived.

A total of thirteen remains were discovered between 2007-2018 - teeth, hand, and foot bones, as well as part of a femur - which belong to at least three adult and juvenile individuals. Homo luzonensis would appear to have some physical similarities to more recent human types, but other features hark back to the australopithecines of Africa between two and four million years ago, as well as very early members of the genus Homo. The finger and toe bones are curved, suggesting that climbing was still an important activity for this species. This also seems to have been the case for some australopithecines.

From that evidence it can be seen that luzonensis raises some questions. Was it descended from australopithecines which had migrated out of Africa (itself a startling new idea as it has long been believed that Homo erectus was the first to do this)? Or was it simply an offshoot of Homo erectus in South-East Asia (the most likely option, with recessive, australopithecine-like traits appearing later, once it was marooned on its Philippine island). The latter option would make it a cousin of floresiensis, and would make it likely that other island-bound descendants of erectus will be found in the future.

In addition, given that Luzon was only ever accessible by sea, the find raises questions about how pre-modern human species may have reached the island in the first place.

50,000

Homo sapiens first reached Australia after spreading slowly through South Asia and Sunda-land. Lowered sea levels - caused by the ice age - had created a landbridge which meant that the South Asian islands were joined together above sea level as far south as Java.

It was thought that the peopling of Australia had been a long-term process involving numerous subsequent movements of people out from Asia. DNA evidence of the twenty-first century seems to suggest the opposite - a short-term process, perhaps even a one-off event, in which one group of unknown size made the journey and became the ancestors of all later aboriginal Australians.

Two routes were possible for the journey into Australia: one from southern China through the Philippines and into New Guinea, the second from South East Asia through the islands of Indonesia and into northern Australia.

Although the frequent lowering of sea levels during ice ages caused the Sunda shelf to become fully exposed, and the same thing happened to the Sahul shelf - comprising Australia, New Guinea, and Tasmania - the two were never linked. Both of the colonisation routes therefore required a sea journey of at least sixty kilometres of open sea, so sea-going craft would have been essential, something which was beyond the technology of these people to construct. What these groups of Homo sapiens used for this so far remains unknown.

Settlement in Sahul-land expanded rapidly, with the southern and eastern areas becoming fully occupied within 25,000 years. During this time the environment changed quite dramatically, becoming increasingly dry and reaching a peak of aridity 18,000 to 16,000 years ago, followed by a slight improvement in conditions. The same dramatic changes brought about the extinction of the giant marsupials at the end of this period.

After 40,000 years of Homo sapiens settlement on Sahul-land, rising sea levels cut off New Guinea and Tasmania, and covered the rich coastal sites. This was simultaneous with the appearance of another variety of human type in Australia, fully modern but with a heavy robust skull. These individuals may be a later wave of immigrants, but it is also possible that they are the result of local breeding effects on a small community.

50,000

Homo erectus
Part 4 of 4

Homo erectus was still in existence in Java at this time, but probably not for long.

Recent studies into the complicated stratigraphy of the Java Homo erectus sites have revealed some surprising information. Researchers have dated deposits which were thought to contain erectus fossils near the River Solo in Java to only 50,000 years ago. This would mean that at least one population of Homo erectus in Java was contemporary with Homo sapiens which had entered the region at least ten thousand years before.

The two species had some level of direct contact, as is proven by the distribution of lice. Lice have stuck with hominids and their primate ancestors for at least twenty million years, and their lineages are remarkably close to those of the hominids.

The distribution of lice around the world proves that there was either some interbreeding on a limited scale between erectus and sapiens, or that sapiens hunted erectus for food and the lice were transmitted during the process of preparing the meat. This very individual strain of lice (found only in the Americas) was then carried by sapiens as they headed northwards towards Beringia. The first wave of humans arrived there around 48,000 years ago, from where they could cross into North America.

Homo erectus may have held on in Java for another 20,000 years before it died out totally. By that stage it had long since been out-competed to extinction by its sapiens cousin.

45,000

Homo neanderthalis
Part 2 of 3

Something happened which transformed the world of Homo neanderthalis, especially in Europe. There was a sudden change in the weather. The climate in Europe began to deteriorate significantly, getting colder and drier. Although this had happened before, during other gaps between ice ages, this was different. The changes were more rapid, and very unsettled, with no particular pattern emerging. And they were simply getting worse and worse.

Neanderthals were built to survive the cold, but the speed of this climate change was different to anything they had experienced before. These changes were not happening at a scale of thousands of years. Instead, sometimes they were at a scale of tens of years or hundreds of years, within the space of a few Neanderthal generations.

They faced a crisis of survival. The forests in which they lived were dying out because of the weather. And in this new, more open landscape, they would have found it increasingly difficult to hunt. Neanderthal hunting methods - on the edge of woodland where their prey wouldn't see them coming - just wouldn't work so well on open steppe environments because the size and weight of their heavy spears made them almost useless for throwing any distance.

40,000

Homo sapiens
Part 5 of 6

Homo sapiens' 'troop-to-tribe' transition seems to have involved systems of gift exchange between distant peoples. Beads made out of ostrich eggshell seem to have been important items in this system of gift-giving, as they are today amongst South African !Kung San hunter-gatherers.

The earliest examples of these beads have been dated to 40,000 years old. They were exchanged over areas which encompass two hundred kilometres in order to secure future favours when times became tough. In this way, humans increased the likelihood of survival, or 'spread the risk of survival'. Gift-giving was a key activity of early modern humans, as it is today.

Another important innovation after 70,000 years ago is the invention of a stone tool technology called 'microliths' in Africa. Microliths are small flakes and blades which characterise the Later Stone Age in Africa. These tools are very diverse, because each was specialised for a task. Previous stone technologies were toolkits to provide a jack-of-all-trades (and master of none), whereas microliths reflect modern humans using the right tool for the right job.

40,000

Homo neanderthalis
Part 3 of 3

At the same time as Homo sapiens was perfecting its 'troop-to-tribe' transition, it also began migrating into Europe for the first time. Once there, modern humans quickly began to compete with the indigenous Homo neanderthalis population for food and resources - something which they had already done very successfully in the Near East.

Neanderthals were already facing problems thanks to abrupt climate change (suffering various related problems which were highlighted in a 2019 study, as covered in the media - see links), so when the first Homo sapiens arrived in northern Europe with their new technology - a much lighter spear which could be thrown - Neanderthals were hit again with the blow of being out-hunted.

In fact, it could have been Neanderthal's loss of dominance in Europe which opened the door for Homo sapiens to begin moving west from Anatolia and competing directly with them. Homo sapiens was established across all of habitable Europe within five thousand years.

24,000

What characterised all Neanderthals was their extraordinarily short lower limbs, built for power but not so good for speed or long distance running. They also had a pelvis which itself was extraordinarily broad. This meant that the pelvis was not going to be as bio-mechanically efficient in long distance locomotion as that of Homo sapiens.

It seems that the very features which made Neanderthals perfectly adapted to the rigours of the ice age had also locked them into an evolutionary dead end. Homo sapiens may not have been adapted to the cold, but they were tailor made for the open plains. They were better able to exploit the open spaces, the steppe habitats which were expanding in ice age Europe. And as the forest retreated, the Neanderthals retreated along with them.

Unable to survive in the open, Neanderthals could only have clung on in ever decreasing woodland refuges. And as their habitat collapsed around them their population fell.

The effect seems to be that the populations which were once closely connected across Europe began to get fragmented and scattered. There came a point at which these populations were no longer viable and the Neanderthals became extinct, with their last communities on the western edges of Europe, in modern Portugal and southern Spain, disappearing.

20,000

Homo denisovan
Part 4 of 4

Homo denisovan still existed at this time, but at the moment, this recently-discovered cousin of H sapiens is mostly a mystery. Populations certainly existed in the Altai Mountains in Siberia, but also on the Tibetan Plateau (see 160,000 years ago).

Research in 2011 showed that modern humans and archaic humans, or Homo denisovan in this specific case, were interbreeding on the mainland of East Asia.

A study indicated that people in East Asia share genetic material with Denisovans, suggesting that the modern human ancestors of East Asians interbred with Denisovans around this time.

Previous studies indicated the occurrence of two separate hybridisation points between archaic humans - genetically and morphologically different from modern humans - and modern human ancestors after leaving Africa. One occurred between Neanderthals and modern humans and the other between Denisovans and ancestors of Oceanians.

But the latest study indicates that hybridisation also occurred in East Asia. This was determined using genotype data, which greatly expands the database. Recent studies (since 2010) have been limited to using complete genomes of modern humans, only available from comparatively few individuals. Genotype data, on the other hand, is currently available from thousands of individuals. Using advanced computer simulation, the genotype data was compared with the genome sequence data derived from bones recovered from Neanderthal locations and the single known Denisovan location.

Findings showed that modern individuals, mainly from South-East Asia, have a higher proportion of Denisova-related genetic variants than people from other parts of the world, such as Europe, the Americas, western and Central Asia, and Africa. Genetic material from these archaic humans lives on to a greater extent than was previously thought, although very little is known of the history of these groups and when their contacts with modern humans occurred.

14,500

Red Deer Cave People (archaic humans)
Part 3 of 3

In 2012, what seems to be the remains of a previously unknown human species were identified in southern China. The bones, which represented at least five individuals, were dated to between 11,500 and 14,500 years ago.

They were named simply the Red Deer Cave people, after one of the sites from which they were unearthed, at Maludong (or Red Deer Cave), near the city of Mengzi in Yunnan Province. A further skeleton was discovered at Longlin, in neighbouring Guangxi Province. The skulls and teeth from the two locations are very similar to each other, suggesting they are from the same population.

The Red Deer Cave people have a mix of archaic and modern characteristics. In general, the individuals had rounded brain cases with prominent brow ridges. Their skull bones were quite thick. Their faces were quite short and flat and tucked under the brain, and they had broad noses. Their jaws jutted forward but they lacked a modern-human-like chin. Computed Tomography (X-ray) scans of their brain cavities indicate they had modern-looking frontal lobes but quite archaic-looking anterior, or parietal, lobes. They also had large molar teeth.

One theory for the origins of this group posits that they represent a very early migration of a primitive-looking Homo sapiens which lived separately from other forms in Asia before dying out. Another possibility contends that they were indeed a distinct Homo species which evolved in Asia (out of Homo erectus) and lived alongside Homo sapiens until remarkably recently.

A third scenario being suggested by scientists not connected with the research is that the Red Deer Cave people could be hybrids. A fourth is that they were Homo sapiens who evolved more primitive features independently because of genetic drift or isolation, or in a response to an environmental pressure such as climate.

A good deal more investigation is required before any decision on this new find can be made.

11,800

Homo sapiens
Part 6 of 6

A new wave of Homo sapiens crossed the frozen Baring Straits - Beringia - and entered the Americas.

However, it has been shown (increasingly in more recent years) that this was not the first migration of modern humans from Asia into the Americas. A date around 40,000 years ago for the very first of them still cannot be discounted, although a definitive date will be almost impossible to pin down. This issue has caused years of controversy, although it was proven without doubt in 2011 that those scholars who were sticking to the 'Clovis culture first' idea were now definitely mistaken.

A mastodon rib was dated precisely to 11,800 years ago and was found to have a projectile point lodged in it.

This placed it before the so-called Clovis hunters, although in truth, the 'Clovis first' model, which stuck firm with the idea that America's original human population swept across a land-bridge from Siberia some 11,000 years ago, had looked untenable for some time.

A succession of archaeological finds right across the United States and northern Mexico had already indicated that there was human activity much earlier than this - perhaps as early as 13-14,000 years ago. It was the mastodon rib which clinched it.

The specimen has actually been known about for more than thirty years. It was found in the late 1970s near Manis, just north of Seattle, in Washington State, on the US west coast - an ideal location on the route for migrating humans arriving from Asia. It is plainly from an old male animal which had been attacked with some kind of weaponry.

DNA investigation also threw up a remarkable irony - the point itself was made from mastodon bone, proving that the people who fashioned it were systematically hunting or scavenging animal bones to make their tools.

This species, Homo sapiens,  was now the most successful ever, having colonised and thrived on all six habitable continents and having also out-competed all related Homo species.