Scientists have a general idea of how we became human, but there
are still some big mysteries to solve.
- Why do we walk upright?
- Why don't we have fur?
- How did our brain become bigger?
Have a look at this cartoon from the New Scientist:
What do we know about human evolution?
There is still a lot we don't know about how we, Homo
sapiens, evolved. Scientists are piecing the puzzle
together.
Modern humans, along with other great apes, evolved from a
common ape-like ancestor. Early humans evolved around 7 million
years ago.

Model of Homo habilis, an early
human (c) Lillyundfreya
Over the past 7 million years, there have been over 20 different
species of early humans. They are all extinct, except us.
Our ancestors evolved in Africa and stayed there for three to
four million years. Eventually our ancestors stood on two legs and
developed a bigger brain. The first species to leave Africa and
spread across the globe was Homo erectus.
Neanderthals
As early humans spread out, the climate was changing. Some
species adapted to the changing world. Others went extinct. Our
most famous extinct relative is Homo neanderthalensis -
the Neanderthals.

Model of a Neanderthal man (c)
Christopher
Cagé
Neanderthals were a very successful species and shared the
planet with us - Homo sapiens. Why did Neanderthals go
extinct? Did they fight with Homo sapiens? Or did a
changing climate kill them?
Neanderthals looked quite different from us and behaved
differently. But what if they weren't as different as they looked?
Perhaps Homo sapiens bred with Neanderthals, leading to
modern humans as we know them. Maybe you have some Neanderthal
genes!
Neanderthals and all other early human species went extinct. We
still don't know why. Modern humans were the only human species to
survive. We spread out across the globe, colonising almost every
continent.