Humans first appeared on Earth at least 315,000 years ago. This figure is based on fossil remains found in Jebel Irhoud, Morocco – the earliest-known remains of modern humans.
The exact time humans first appeared is difficult to judge because species don’t come into being overnight. Rather, they change and evolve slowly from ancestral species.
Because the first human remains date back to around 315,000 years ago, our species will therefore have appeared some time before this. DNA evidence from human chromosomes indicates that humans (scientific name: Homo sapiens) may have first appeared more than half a million years ago.
This may sound like a long time, but the ancestral species that gave rise to the early humans found in Morocco all arose in Africa, and their history stretches back even further, to some six million years in the past.
The evolution of these ancestral species is characterized, in particular, by the development of progressively larger and more complex brains.
Read on to find out more about the amazing story of human evolution...
Page Index
- Where did humans first appear?
- The human family tree
- What are Australopithecines?
- Which are the closest prehistoric relatives of modern humans?
- What did early Homo sapiens look like?
- How did modern humans spread around the world?
- Further Reading And References
Related Pages
- Primates: The Ultimate Guide – Facts, Pictures, In-Depth Information
- Monkey Facts: The Ultimate Guide to Monkeys, With Pictures & In-Depth Information
Where did humans first appear?
The very oldest human fossils come from Africa; this includes those from Jebel Irhoud, along with others from Ethiopia in East Africa (dated at 196,000 and 160,000 years ago). This has led archaeologists to conclude that our species evolved in Africa.
In fact, the majority of the approximately 6,000 prehistoric human fossils that have been excavated have been found in Africa; this indicates that human evolutionary history, on this continent, dates back to the time when the human lineage (hominins) split from the chimpanzees, some six million years ago. This is why Africa is known as the “cradle of humankind”.
INTERESTING FACT: Humans are mammals in the family Hominidae (the “great apes”), which includes chimpanzees, gorillas and orangutans. Although the great apes are closely related to us, they are not our direct ancestors and we did not evolve from them.
The family Hominidae is part of a larger group: the order Primates. Other primates include lorises, lemurs, monkeys and gibbons.
Early Homo sapiens arose from ancestral species although we don’t know exactly which species were our direct ancestors. This is because the human fossil record contains not only examples of species that were our ancestors, but also species that instead became extinct.
Since many fossil deposits consist of incomplete skeletons, or just a few bones, it is very difficult to identify the exact relationships between different species. In addition, archaeologists regularly find and name new species, which makes things even more complicated.
The human family tree
Human evolution does not involve one ancestral species changing into the next, in a long line of inevitable steps towards modern H. sapiens. Instead, our evolutionary history looks more like a tree, with many different prehistoric species scattered along the trunks and branches.
Some species have not given rise to new species and, thus, they mark evolutionary dead ends; they have simply become extinct. Others have changed gradually into new species; living humans carry the genes of their ancestors, going back many millions of years.
INTERESTING FACT: We share 98.8% of our DNA with chimpanzees, our closest living relatives. This means that our genetic code differs by 1.2%. In contrast, humans differ from each other by an average of only 0.1%
The human family tree contains several groups of important ancestors. Among these groups are the australopithecines and the members of the genus Homo.
What are Australopithecines?
This group of early human ancestors, all in the genus Australopithecus, probably evolved in eastern Africa around 4.5 million years ago. They spread throughout the African continent, where their fossils are found in many places. They became extinct around 1.9 million years ago.
The australopithecines were bipedal (walked on their back legs), although they still spent time climbing trees. They had body proportions similar to those of a chimpanzee.
They stood only just over a meter in height, and had brains about one third of the size of a modern human’s. In addition, their faces were sloped, with the lower jaw protruding, similar to the face of a chimpanzee. If you saw one today, you would consider it more like an ape than a human.
Which are the closest prehistoric relatives of modern humans?
Sometime just over two million years ago, the genus Homo emerged from the group of Australopithecus species.
Homo habilis
The earliest representative of the genus Homo is Homo habilis, the ‘handy man’, so named because of his skill at making and using stone tools. Homo habilis is believed to have lived from around 2.3 million years ago.
Although the brain size of H. habilis individuals was a bit larger than found in the australopithecines, it was still only half the size of a modern human’s brain. These were hominins with a small stature, that also climbed trees, as well as walking with an upright posture.
Homo erectus
Homo erectus, upright man, appeared in the fossil record around 1.9 million years ago. It is unclear whether H. erectus evolved directly from H. habilis, but it is known that the two species co-existed in East Africa about 1.5 million years ago.
This is the first of the ancient human ancestors that had body proportions similar to ours; the legs were longer, and the arms shorter. This was clearly a species that was adapted to living on the ground, rather than in the trees.
Homo erectus is also the first of our ancient ancestors to have expanded its range out of Africa. Fossils of H. erectus have been found in south east Asia, eastern Asia, China, Indonesia and Europe. These ancient human ancestors walked to new continents, crossing areas of land that are, today, covered by water.
INTERESTING FACT: Homo erectus is the first species associated with the controlled use of fire. This is the first of our ancestors that ate cooked food.
It is now accepted that, although Homo erectus lived on earth for around two million years, and spread through Africa and large parts of Asia and Europe, not a single population survived into modern times. The populations throughout the world all died out.
INTERESTING FACT: The species Homo erectus survived on earth for nine times as long as modern humans have been around; H. erectus was clearly very good at adapting to changes in the environment.
Homo neanderthalensis
Homo neanderthalensis, or Neanderthal man, lived in Europe from at least 430,000 years ago. There are many fossils of Neanderthals and we know that they were a bit shorter and stouter than modern humans, and had slightly larger brains.
Neanderthals are not the direct ancestors of modern man, but rather they are like close cousins; it is thought that modern humans and Neanderthals arose from the same common ancestor, perhaps as long ago as 800,000 years.
Neanderthals were excellent hunters and used a variety of different tools. They survived through some very cold conditions, and learned to sew clothing for themselves from the hides of animals. It is also likely that they could communicate using language.
INTERESTING FACT: Modern humans and Neanderthals co-existed in Europe for several hundred thousand years, and even interbred with one another. Today, modern people around the world (excluding people of African origin) carry some Neanderthal genes.
Around 35,000 years ago, the last Neanderthals died out, leaving us, Homo sapiens, as the last and sole surviving representative on earth of a long and fascinating human evolutionary story.
Homo sapiens
Homo sapiens, the thinking man, is thought to have evolved from some of the ancient hominin species in the family tree. We have large brains and are fully bipedal. We have lost the body hair that characterized our earlier ancestors, and we are supreme users of tools.
What did early Homo sapiens look like?
The five people whose remains were found fossilized at Jebel Irhoud in Morocco, and who represent the oldest known modern humans, looked very much like us. Their faces were flat, like ours, and their teeth and jaws were the same, although slightly larger. They did, however, have more elongated skulls, unlike the rounded skulls of modern humans.
How did modern humans spread around the world?
The short answer to this question is that they walked, mostly.
About 70,000 years ago a single, small group of anatomically modern Homo sapiens left East Africa and began to spread eastwards. Along the way they settled, and their populations increased. Further dispersal followed, and the people slowly moved along the southern coast of the Arabian Peninsula, Asia and the Indonesian Islands. Populations reached Australia by 50,000 years ago.
In addition, descendants from the original group also migrated northwards to Europe, arriving some 40,000 years ago. Other descendants populated central Asia and lastly, some 20,000 years ago, the first modern humans arrived in the Americas from Asia. It is thought that some of these early Americans arrived by boat, while others came on foot.
This means that all humans alive today descended from African ancestors. It also means that almost all people living outside Africa can trace their ancestors back to that single, small group that walked out of that land and began a journey to populate the rest of the world.
Further Reading And References
- Primates: The Ultimate Guide – Facts, Pictures, In-Depth Information
- Monkey Facts: The Ultimate Guide to Monkeys, With Pictures & In-Depth Information
References
Alex, B. 2020. Our Ancestor Homo erectus Is 200,000 Years Older Than Previously Thought. Discover. https://www.discovermagazine.com/planet-earth/our-ancestor-homo-erectus-is-200-000-years-older-than-previously-thought
Culotta, E. & Gibbons, A. 2016. Almost all living people outside of Africa trace back to a single migration more than 50,000 years ago. American Association for the Advancement of Science. https://www.sciencemag.org/news/2016/09/almost-all-living-people-outside-africa-trace-back-single-migration-more-50000-years
Gibbons, A. 2015. How Europeans evolved white skin. America Association for the Advancement of Science. https://www.sciencemag.org/news/2015/04/how-europeans-evolved-white-skin
Gibbons, A. 2017. World’s oldest Homo sapiens fossils found in Morocco. America Association for the Advancement of Science. https://www.sciencemag.org/news/2017/06/world-s-oldest-homo-sapiens-fossils-found-morocco
Pringle, H. 2012. The first Americans. Scientific American. https://www.scientificamerican.com/article/the-first-americans/
Sharping, N. 2020. When did Homo sapiens first appear? Discover. https://www.discovermagazine.com/planet-earth/when-did-homo-sapiens-first-appear
Smithsonian National Museum of Natural History. 2020. What does it mean to be human? Smithsonian National Museum of Natural History https://humanorigins.si.edu/evidence/human-fossils
Suntsova, M. V., & Buzdin, A. A. 2020. Differences between human and chimpanzee genomes and their implications in gene expression, protein functions and biochemical properties of the two species. BMC Genomics 21, 535 (2020). https://doi.org/10.1186/s12864-020-06962-8
Than, K. 2007. Fossils Could Force Rethink of Human Evolution. LiveScience. https://www.livescience.com/1756-fossils-force-rethink-human-evolution.html#:~:text=Peaceful%20coexistence&text=In%20contrast%2C%20H.- abilis%20and%20H.,Meave%20Leakey%2C%20Richard%20Leakey's%20wife.
Wikipedia. 2020. Early human migrations. Wikipedia Inc. https://en.wikipedia.org/wiki/Early_human_migrations#Dispersal_throughout_Africa
Your Genome. 2016. Evolution of modern humans. Your Genome. https://www.yourgenome.org/stories/evolution-of-modern-humans
