We weren’t alone! Scientists confirm there were two other species of early human beings
- Skulls from flat faced early humans found in ‘cradle of life’ near Lake Turkana in Kenya
- Scientists believe the new species eventually came to an evolutionary dead end
By Mark Prigg
PUBLISHED:17:16 EST, 8 August 2012| UPDATED:07:01 EST, 9 August 2012
Scientists have discovered two new species of early human which lived alongside our direct ancestor two million years ago, before coming to an evolutionary ‘dead end’.
The revelation is based on three new fossils unearthed between 2007 and 2009 from a site near Lake Turkana in Kenya – known as the ‘cradle of mankind’.
They included a face, a near-complete lower jaw, and part of a second lower jaw.
Combined with a mysterious fossil known as ‘1470’ found nearby four decades ago, they confirm the existence of a human species with a large brain case and long, flat face.
The fossils appear to be distinct both from Homo erectus and Homo habilis, another primitive species from the same era.
Before the new discoveries, experts had tentatively named the 1470 species Homo rudolfensis.
The fossils were unearthed by the Koobi Fora Research Project led by Professor Meave Leakey and are between 1.78 and 1.95 million years old.
They were found just over 10 kms from 1470’s location.
Dr Leakey, whose findings are published in the journal Nature, said: ‘For the past 40 years we have looked long and hard in the vast expanse of sediments around Lake Turkana for fossils that confirm the unique features of 1470’s face and show us what its teeth and lower jaw would have looked like.
‘At last we have some answers.’
Dr Leakey said one of the most noticeable features of 1470 was its strong jaw.
‘The cheek bones are so far forward it means they would have been able to use quite a strong biting force,’ she said.
It is also believed we got on well with our new ancestors.
‘Modern primates are generally very good at living together,’ Leakey said.
‘You can see troops of monkeys composed of at least two species, if not more.’
Co-author Professor Fred Spoor, from University College London, said: ‘Combined, the three new fossils give a much clearer picture of what 1470 looked like.
‘As a result, it is now clear that two species of early Homo lived alongside Homo erectus.
‘The new fossils will greatly help in unravelling how our branch of human evolution first emerged and flourished almost two million years ago.’
Bernard Wood, professor of anatomy at George Washington University in Washington FC, reviewed the study for the journal and said the evidence for at least two Homo lineages as early as two million years ago is ‘compelling’.
He said: ‘The task of palaeoanthropologists is to reconstruct the evolutionary history of the period between our species, Homo sapiens, and the ancestral species we share exclusively with chimpanzees and bonobos.
‘There must have been a ladder-like sequence of species connecting us with that common ancestor; but it is unclear whether our section of the ‘tree of life’ is restricted to this ancestor- descendant sequence, or whether it includes other, now extinct, lineages.
‘Might there have been multiple lineages early in the history of our own genus, Homo?’
Scientists have seen many different species of other animals evolve with different traits.
If the new trait is better suited to the environment then the new species thrives, if not it becomes extinct.
According to Professor Chris Stringer of the Natural History Museum in London, fossil evidence is increasingly suggesting that human evolution followed the same pattern.
‘Humans seem to have been evolving in different ways in different regions’ He told the BBC.
‘It was almost as if nature was developing different human prototypes with different attributes, only one of which, an ancestor of our species, was ultimately successful in evolutionary terms,’ he said.