Lucy's ancient human ancestor was less intelligent than a monkey, the study claims – questioning how bright our early cousins are
- Lucy had long thought of as smart as big monkeys, as she had brains of similar size
- However, the researchers found that blood flowed to her brain at a slower rate
- They did this by measuring the size of the holes in the skull that entered the arteries
- The level of intelligence is strongly indicated by the rate of blood flow to the brain
- We probably got intelligence quickly because of social complexity, not brain size
Early human ancestors like Lucy may have been less intelligent than today's great apes – such as chimpanzees, gorillas and orangutans – one study showed.
Lucy, so called Australianopticals was one of the first early humans, sporting a relatively small brain compared to us, but with different human characteristics.
Researchers had previously assumed that Lucy had similar intelligence to large apes, based on the fact that they all had similar brains.
However, the researchers found that – despite this – blood flowed less rapidly into the brains of Atralopathy than those of modern large apes.
In fact, tiny, window openings like arteries in the skulls of modern monkeys would allow twice the rate of blood flow to the brain.
The rate of blood flow to the brain is known to be indicative of both the rate of brain metabolism and the level of intelligence.
According to the researchers, the findings show that intelligence has evolved much faster in modern human species, probably in keeping with the growing social complexity.
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Early human ancestors like "Lucy" depicted in this reconstruction may have been less intelligent than today's great apes – such as chimpanzees, gorillas and orangutans – a study found
WHO IS "HUMAN"?
"Lucy" is the fossilized remains of a female Australian-American affair, one of the oldest early humans.
Lucy was unearthed from a paleontological excavation site called Jadar in northern Ethiopia in 1974.
The remnants – which make up 40% of the complete skeleton – date back 3.2 million years.
He had a small skull and was walking upright – though some experts believe he may have spent time living on trees.
In 2016, researchers suggested Lucy die by falling from a tree.
Evolutionary biologist Roger Seymour of the University of Adelaide and his colleagues measured the sizes of the channels passing through the skulls of living large apes and compared them with those found in the fossilized skulls of human ancestors.
Among the species studied by researchers were gorillas, orangutans, and monkeys – which include chimpanzees and bonobos.
They also looked at modern humans (Homo sapiens) and our distant "cousins" of three million years, the Australian.
The size of these channels reveals the rate at which each animal was able to provide blood flow to its brain – which in turn is related to both the metabolic rate of the brain and intelligence.
Researchers have found that modern gorillas have twice the rate of blood flow to the arteries that pass through these canals than Australopithecus did, even though they all have similar brains.
In addition, the team reports that even monkeys with smaller brains – specifically chimpanzees and orangutans – have higher blood flow rates to their brains than Australopathy.
On the other hand, this would suggest that Australians like Lucy were less intelligent than modern chimpanzees, gorillas and orangutans.
"Lucy" is the fossilized remains of a female Australian-American affair, one of the oldest early humans. The remnants – which make up 40% of the complete skeleton – date back 3.2 million years. In the picture, a reconstruction of Lucy's skull based on existing fragments
The team reports that even monkeys with smaller brains – specifically chimpanzees, images and orangutans – have higher blood flow rates to their brains than Australopathy
"The results cast doubt on the idea that the neurological and cognitive traits of recent large apes adequately represent the abilities of the species of australopithecines," the researchers wrote in their paper.
"The use of modern primates as a proxy for the evolution of hominin may have historically prevailed due to similar brain sizes."
The fact that gorillas have twice the rate of cerebral blood flow from Australopathy is "surprising", the researchers noted.
Lucy was excavated from a paleontological excavation site called Jadar in northern Ethiopia in 1974
"The astralopithecus is located between large apes and humans on the basis of several measures related to the brain and intelligence," they added.
"Obviously, the underlying assumptions that cognitive ability, brain metabolism and blood flow rates at all brain size scales parallel – and that patterns apparent in living primates relate to hominins – are incorrect."
The full findings of the study were published in the journal Proceedings of the Royal Society B.
WHEN DO YOU REPEAT AMERICANS?
The timeline of human evolution can be traced back millions of years. Experts estimate the family tree goes as follows:
55 million years ago – The first primitive primates are developing
15 million years ago – Hominidae (big apes) evolve from ancestors to gibbon
7 million years ago – First, the gorillas are developing. Later, chimpanzees and human species differ
Similar is the recreation of the Neanderthal man
5.5 million years ago – Ardipity, early 'proto-human' share traits with chimpanzees and gorillas
4 million years ago – Ape like the early people, australopetins appeared. They had brains not bigger than chimpanzees, but other more human characteristics
3.9-2.9 million years ago – Australoipithecus afarensis lived in Africa.
2.7 million years ago – Parantrop, lived in the woods and had great chewing jaws
2.6 million years ago – Hand axes are becoming the first major technological innovation
2.3 million years ago – Homo habilis was first thought to have appeared in Africa
1.85 million years ago – First & # 39; modern & # 39; a hand appears
1.8 million years ago – Homo ergaster begins to appear in fossil record
800,000 years ago – Early humans control fire and create fires. The size of the brain increases rapidly
400,000 years aga – Neanderthals first begin to appear and spread throughout 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