LUCY

                                                                   LUCY

Forty years ago, one Sunday morning in late November 1974, a research team was excavating a site remote Afar region, Ethiopia.
For a survey of the area, paleoanthropologist Donald Johanson discovered a small piece of bone from his elbow.
He immediately realized that it was a human ancestor. He found many remains more.
"When I looked to my left I saw bits of a skull, a piece of jaw and a pair of vertebrae," says Johanson.
It was evident that the discovery of the skeleton represented a milestone: the sediments in the area had 3.2 million years old.
"I realized it was part of a skeleton of more than three million years," says the scientist.
He was the oldest hominid that had been found.
When I looked to my left I saw bits of a skull, a piece of jaw and a pair of vertebrae. I realized it was part of a skeleton of more than three million years
Donald Johanson, a paleoanthropologist
Later I also learned that was the most complete: 40% of the skeleton was preserved.
At night, in the camp, Johanson put a cassette that had brought the Beatles and "Lucy in the Sky with Diamonds" rang.
Because of its size, Johanson believed that the skeleton was of a woman.
"Why do not you call her Lucy?" Someone said. The suggestion fell like a glove. "Suddenly," recalls Johanson, "she became a person passed about four years before Lucy was officially described. It belonged to a new species called Australopithecus afarensis and it was evident that he was one of the most important fossils ever discovered.
But the next morning finding, researchers discussion was dominated by a series of questions.
How old was Lucy when she died? Did he have children? How was it? Is our direct ancestor, the missing link in the chain of the human family? Forty years later, science is beginning to answer some of these questions
Although it was a new species, Lucy was not the first Australopithecus found. It was the Taung child, a fossilized skull of a young boy who lived about 2.8 million years ago in Taung, South Africa.
It was found in 1924 and analyzed by the anatomist Raymond Dart. Dart realized that belonged to another species called Australopithecus africanus.
I knew with a look that I had in my hands was not an ordinary (...) ape brain. It was a brain replication three times larger than that of a baboon and considerably larger than that of an adult chimpanzee.
His teeth were more like those of a human being than to those of an ape. Dart also concluded that he could walk upright like a human because of his skull, where the spinal cord meets the brain had a human form.
The Taung Child was the first fossil that gave us a clue that humans had originated in Africa. But when Dart published his analysis was widely criticized. At that time, it was thought that Europe and Asia were crucial to human evolution ..
His teeth were more like those of a human being than to those of an ape. Dart also concluded that he could walk upright like a human because of his skull, where the spinal cord meets the brain had a human form.
The Taung Child was the first fossil we Taung Child was the first fossil that gave us a clue that humans had originated in Africa.
But when Dart published his analysis was widely criticized. At that time, it was thought that Europe and Asia were crucial to human evolution.

When Lucy appeared, anthropologists accepted that early Australopithecines were human beings, not just apes.Lucy belongs to the species called Australopithecus afarensis..
  

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Although it was a new species, Lucy was not the first Australopithecus found. It was the Taung child, a fossilized skull of a young boy who lived about 2.8 million years ago in Taung, South Africa.
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His teeth were more like those of a human being than to those of an ape. Dart also concluded that he could walk upright like a human because of his skull, where the spinal cord meets the brain had a human form.
The Taung Child was the first fossil that gave us a clue that humans had originated in Africa.
When Lucy appeared, anthropologists accepted that early Australopithecines were human beings, not just apes.
What was Lucy? This was one of the first questions that arose.
  The finding gave weight to the theory that our evolution was not linear.
His skull, jaw and teeth were like those of an ape than other Australopithecus.

The place was jammed the brain was very small, no larger than a chimpanzee.
He had a strong jaw, a small forehead and long, hanging arms.
Johanson realized immediately that walked upright by the shape and position of your pelvis.
His knees and ankles also reflected that walked on two feet.
This reinforced the idea that upright walking was one of the selective pressures that pushed humanity forward.
Walking, an exclusively human trait
It is believed that Lucy lived in a small social group. Probably in a polygamous society.
The first hominids did not need a bigger brain to move away evolutionarily apes.
The extra brain power came only a million years later with the appearance of Homo erectus.
Although the larger brain would be important later, walking is one of the traits that make us uniquely human.
But also, Lucy spent time in trees.
And maybe it's push to walk as a way to approach the branches that were too flexible to ride them.
Change in diet
It is unknown why Lucy left the safety of the trees to scroll through the floor.
One theory is that they could have done to find food, says Chris Stringer of the Natural History Museum, London.
In the same vein, recent evidence indicates that there was a change in the diet of Australopithecines.
The diet of several species, according to evidence found in the remains preserved in teeth homínidos-, including Lucy, began to expand 3.5 million years ago.
More delayed species such as Homo erectus used tools.
Besides fruits, they began to eat grass and reeds and possibly meat.
This may have allowed them to travel and move more efficiently in a changing environment.
How this processed food? Other later species such as Homo erectus, using simple tools, but have not been found so old tools.
However, in 2010, animal bones were found with marks that appear to have been made by stone tools.
This could indicate that Lucy and her relatives employed stone tools to eat meat.
in society
According fossils found in Hadar, Lucy seems to have lived in a small social group.
She was small in comparison with men of his kind. This has led to think that their society was dominated by men.
It could have been a polygamous society such as gorilla groups today.
Usually, males are considerably larger in species where a male controls several females.
midpoint
It also appears that Lucy's childhood was shorter than ours and had to fend for herself since childhood.
We know that because he was an adult wisdom teeth and bones were fused.
I trust you will find fossils that range, because I know that there are four areas of study fossil sediments that time in Ethiopia
But, unlike modern humans, seems to have grown to their size very quickly. He died at age 12, and his brain reached its final size faster than ours.
In short, Lucy was something halfway between apes and humans.
Where then lies in our family tree?
Apparently, Lucy takes us back to our common ancestor with chimpanzees as previously thought.
Recent genetic studies indicate that chimpanzees parted long before, perhaps even 13 million years ago.
If so, Lucy arrived quite late in the history of human evolution.
However, even more around the idea that A. afarensis is our direct ancestor problem is that our lineage is quite complicated.
There were many species of early hominid -have found at least 20- who lived side by side and probably mixed.
We do not know is what gave rise to Homo sapiens and which, from the point of view of evolution, came to a standstill.
  The extra brain power came only a million years later with the appearance of Homo erectus.
But Tim White, a researcher at the University of California, US, believes the sort of Lucy remains the best candidate to direct ancestor, but believes it takes to find more fossil evidence of that period.
"I am confident that we will find fossils that range, because I know that there are four areas of study fossil sediments that time in Ethiopia," says White.
Lucy's discovery marked a turning point in our understanding of human evolution.
Even today, scientists continue to learn through it.
The contribution of Lucy
According to Johanson, his most important contribution was to promote a wave of investigations that resulted in the discovery of many new species, such as Ardipithecus and A. sediba.
Thanks to these findings we now know that the evolutionary process that culminated in us was not linear.
There were variations and experimentation in the way, and many species became extinct, like the Neanderthals.
As every year, the team Johanson soon begin to dig into the Afar region of Ethiopia, near where Lucy was found.
You may find more fossils. But even if the encounter, since 1974 there have been many more complete and fossils older than Lucy.
However, there is no doubt that Lucy has already secured a place in the history of human evolution.

BBC. UK