The modern human brain has evolved 1.7 million years ago, research shows

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Modern human brains are ‘relatively young’, evolving only 1.7 million years ago after the first humans first spread from Africa, a new study claims.

Researchers used computed tomography to examine the skulls of Homo fossils that lived in Africa and Asia between 1 million and 2 million years ago.

They then compared the results of their analysis with today’s humans and our closest relative – chimpanzees and other great apes.

They pinpointed the development of a humanoid brain somewhere between 1.5 and 1.7 million years ago in Africa – a little over a million years before the first Homo sapiens emerged.

The researchers used computed tomography to examine the skulls of Homo fossils that lived in Africa and Asia 1 to 2 million years ago.  They then compared the fossil data with reference data from great apes and humans.  Pictured, early Homo skulls from Georgia with ape-like brain (left) and from Indonesia with a humanoid brain (right)

The researchers used computed tomography to examine the skulls of Homo fossils that lived 1 to 2 million years ago in Africa and Asia. They then compared the fossil data with reference data from great apes and humans. Pictured, early Homo skulls from Georgia with ape-like brain (left) and from Indonesia with a humanoid brain (right)

“Our analyzes suggest that modern human brain structures did not emerge in gay African populations until 1.5 to 1.7 million years ago,” said study author Christoph Zollikofer of the University of Zurich.

Researchers say the human brain as we know it evolved as the stone tool culture in Africa became increasingly complex, but a short time later, the new Gay populations spread from Africa to Southeast Asia.

There are four living classifications of great apes or ‘Hominidae’ – Orangutan, Gorilla, Pan (consisting of chimpanzee and the bonobo) and Homo, of which only modern humans remain.

Humans today are fundamentally different from other great apes – mainly because we live on the ground, walk on two legs, and have much larger brains.

Skull of early Homo from Dmanisi, Georgia showing the internal structure of the brain sheath and the inferred brain morphology

Skull of early Homo from Dmanisi, Georgia showing the internal structure of the brain sheath and the inferred brain morphology

Skull of early Homo from Dmanisi, Georgia showing the internal structure of the brain sheath and the inferred brain morphology

The first populations of the genus Homo arose in Africa about 2.5 million years ago.

They were already walking upright, but their brains were only half the size of humans today.

These earliest gay populations in Africa had primitive ape-like brains – just like their extinct ancestors, Australopithecus.

Australopithecus anamensis is the oldest known member of the genus Australopithecus. It is generally believed that our own gender, Homo, originated from this group.

These earliest gay populations in Africa had primitive ape-like brains - just like their extinct ancestors, Australopithecus.  Australopithecus anamensis is the oldest known member of this genus

These earliest gay populations in Africa had primitive ape-like brains - just like their extinct ancestors, Australopithecus.  Australopithecus anamensis is the oldest known member of this genus

These earliest gay populations in Africa had primitive ape-like brains – just like their extinct ancestors, Australopithecus. Australopithecus anamensis is the oldest known member of this genus

Timeline of when human ancestors started walking upright

55 million years ago – First primitive primates to evolve

15 million years ago – Hominidae (great apes) evolve from the ancestors of the gibbon

Seven million years ago – There is a primate that lives in the trees and swings. He cannot walk on two legs.

This species diverged into two sexes, one would give birth to humans, the other would give rise to bonobos and chimpanzees.

4.4 million years ago – Ardipithecus ramidus exists. The fossil Ardi is one of this kind.

It has hands resembling its ancestor suitable for tree life.

His feet also had a gripping toe, which helped the branch’s life.

3.9-3 million years ago – Lucy, a member of the Australopithecus afarensis species, is alive.

She is believed to be a descendant of Ardi and has a pelvis that indicates she walked upright.

She lacks the ‘gripping toe’ and had hands that were more dexterous than Ardi and ‘had the ability to use human-like precision grips’.

The million years or so between Lucy and Ardi has been described as a “great evolutionary leap.”

First evidence of the use of stone tools.

About 2.8 million years ago – First Homo species evolve from Australopithecus

2 – 1.6 million years ago – On the other branch of this evolutionary family tree, the descendant of the species that lived seven million years ago splits into two different species.

This is how the modern chimpanzee and bonobo came into being.

1.85 million years ago – First truly ‘modern’ hand emerges

400,000 years ago – Neanderthals first appear and spread across Europe and Asia

300,000 to 200,000 years ago Homo sapiens – modern humans – appear in Africa

50,000 to 40,000 years ago – Modern people are reaching Europe

About 40,000 years ago – Neanderthals are dying

Size aside, the human brain differs from that of the great apes, especially in the location and organization of individual brain regions.

“ The characteristics typical of humans are mainly those regions in the frontal lobe that are responsible for planning and executing complex patterns of thought and action, and ultimately language, ” said first study author Marcia Ponce de León at the University of Zurich.

Because these areas are significantly larger in the human brain, the adjacent brain areas shifted further back.

The first gay populations outside Africa – in Dmanisi in present-day Georgia at the intersection of Eastern Europe and Western Asia – had brains as primitive as their African relatives.

However, these early humans were quite capable of crafting countless tools, adapting to Eurasia’s new environmental conditions, developing animal food sources, and caring for group members in need of assistance.

During this period, cultures in Africa became more complex and diverse, as evidenced by the discovery of different types of stone tools.

The researchers think biological and cultural evolution are likely interdependent.

“It is likely that the earliest forms of human language also developed during this period,” said Ponce de León.

Fossils found on the island of Java, which is now part of Indonesia, prove that the new populations were extremely successful, the team said.

Shortly after their first appearance in Africa, they had already spread to Southeast Asia.

They could not support previous theories because of the lack of reliable data.

“The problem is that our ancestors’ brains have not survived as fossils,” Zollikofer said

“Their brain structures can only be deduced from impressions left by the folds and grooves on the inside of fossil skulls.”

Because these impressions differ significantly from person to person, it has not been possible until now to clearly determine whether a particular Homo fossil had a more ape-like or more human-like brain.

Using computed tomography analyzes of a series of fossil skulls, the researchers have now been able to close this gap for the first time.

The new study is published in the journal Science.

Previous research from the University of Zurich found that humans develop fine motor skills later than other primates because we have larger brains that take longer to develop.

While “a big brain equates to great agility,” humans have to wait relatively longer to develop full dexterity, allowing us to tie shoelaces, hold a pen, or use cutlery.

Humans develop motor skills later than other primates because of our larger brains: 2020 study

Great apes like these bonobos have large brains just like humans and can therefore learn very skilled dexterity

Great apes like these bonobos have large brains just like humans and can therefore learn very skilled dexterity

Great apes like these bonobos have large brains just like humans and can therefore learn very skilled dexterity

Humans develop fine motor skills later than other primates because we have larger brains that take longer to develop, biologists in Switzerland reported in July 2020.

While “a big brain equates to great agility,” humans have to wait relatively longer to develop full dexterity, allowing us to tie shoelaces, hold a pen, or use cutlery.

Researchers at the University of Zurich have studied more than 30 different primate species for seven years.

While species of great apes – including homo sapiens – have large brains and can therefore learn very skilled dexterity, they take longer to fully develop, they found.

In comparison, squirrel-like tamarins reach their full potential when it comes to controlling objects faster, but lack the skills of more advanced primates.

Although it takes humans longer to reach the peak of our skill potential, biologists claim to have found a common pattern among the different primate species.

They say the complex motor skills for manipulating food and tools develop at different stages that are evident in almost all primate species.

“ It’s no coincidence that we humans are so good at using our hands and tools, our big brains have made it possible, ” said Dr. Sandra Heldstab, an evolutionary biologist in the Department of Anthropology at the University of Zurich, Switzerland.

“Our results show that neural development follows extremely rigid patterns – even in primate species that differ widely in other respects.”

More: Humans develop motor skills later than other primates