Lucy Paper Essay
For several centuries, it has been researcher’s goal in science to find the human race, ancient ancestry. From the time of Charles Darwin’s, Theory of Evolution, anthropologists, paleontologist and other researchers from various fields have been discovering and identifying human origins. The quest to find human’s oldest ancestor was the missing link in the human evolution tree. The “missing link” was eventually discovered in Hardar, Ethiopia by Dr. Donald Johanson, an American paleoanthropologist.
According to Johanson, Lucy (Australopithecus afarensis) represented the missing link between apes and humans.She was our oldest human ancestor, the ape who walked upright. According to Dr.
Donald Johanson, Lucy was one of the greatest paleoanthropological finds of the 20th century, but to others, Johanson’s discovery and methodology of identifying Lucy had many flaws and contradictions to his theory. In 1972, in Hadar, Ethiopia, Dr Johnason and his research team were on an expedition in search of fossils and artifacts related to human origins. As Johanson and his team explored the area for fossils, Johnason noticed bones of knee joint.
At first he assumed it was bones of an ancient monkey, but shortly noticed that it looked vaguely human.In need of conformation of his findings, Johanson turned to expert advice. Johanson took the knee joint to be examined by Owen Lovejoy, an anatomist. Owen confirmed Johanson suspension, and stated as soon as he seen the knee joint he instantly knew it was that of a human. “Walking upright is something that only humans can do. And it needs a special kind of knee joint, one that can be locked straight. A chimp gets around on all fours. If it tries to walk upright, it’s knee joint doesn’t lock.
It’s forced to walk with a bent leg and that’s tiring” .This important discovery showed an ancient bipedal creature in Johanson theory of finding the “missing link” in human ancestry. The next step in this discovery was getting the age of this fossil. Johanson stated that they could not directly date the fossils but they could date the volcanic ash that the fossils were found in. As stated in PBS In search for human origins.
Johanson describes the dating technique and process. “With the eye of a connoisseur, the geologists selected the best ash samples for analysis back in the lab. Dating techniques are so precise that we only need small samples, as little as one single crystal or grain.
The purest crystals are blasted by an Argon laser we’ve nicknamed Flash Gordon. As it melts, the crystal releases Argon gas. The amount of gas given off gives us a direct estimate of the age of the volcanic ash, and once we know that, we could work out the age of any fossil we found nearby. The results were exactly what we had hoped for. The knee was over three million years old, one of the oldest human fossils ever found” 1. Now with the evidence of the knee joint that was confirmed to be that of a creature that walked upright and an estimated age of over three million years old, Johanson had set off to find what type of creature this was.To continue his search of the oldest human ancestor, Johanson and his team went off on another expedition the following year to discover more of these missing fossils. Johanson and his research team returned back to Hadar, to the place where the original knee joint bone was found.
They began working immediately and worked sun up to sun down looking for more fossils. Suddenly, Johanson relied on a hunch one morning, and stated that while on his way back to camp from the field, he happened to look over his shoulder and noticed small pieces of bones on the surface of the ground.In this search, Johanson had recovered almost an entire skeleton.
As they put the pieces of the skeleton together, excitement rose inside the camp. Recognizing the significant human-ape like features of this skeleton, the team had realized they had found something extraordinary. When the skeleton was finally put all together, they realize it was of a tiny adult female.
They named her Lucy. Dr. Johanson wondered at the time, why was there such a creature that existed at this period in time.
He began to analyze Lucy’s original environment in Africa.Johanson described that the climate in Africa was changing, and there was alternate seasons. There was less rainfall, and as the forest was shrinking, the number of apes declined along with the shrinking forests. Except, that is, for one: Lucy, the ape that stood up. As the food in the forest, became hard to find, Lucy and her kind could survive by collecting food that was across the grasslands. Since she was not on all fours, her hands became free to collect food and this was an advantage she and her kind had over the rest of the apes of the forest.Johanson also noticed some differences in the society that Lucy and her kind lived in compared to the apes and gorilla.
Predominately males were in charge of groups of females and would fight for control. Johanson had notice that because Lucy’s landscaped was different than the jungles and forest, that she had a wider range of food, preventing the need to fight for control. He also used the structure of the teeth, to show that males of Lucy’s kind had small canine teeth like females and this suggested the lack of fighting and that males and females were pair as monogamous couples.Dr.
Johanson based his case for Lucy’s inclusion into the human family primarily on her bipedal ability, and to show that human ancestors walked upright before having intelligence. In his discovery of Lucy, he provided several sources of evidence to justify that Lucy was a bipedal creature that was the oldest human ancestor. In the examination of Lucy’s skeleton, the similarities of Lucy’s knee joint to that of the one that was found the year early was the first piece of evidence that Lucy walked upright.As stated before, a human knee joint must lock straight, in order to be able to walk upright. This knee was identical, indicating that Lucy must have been the same creature that the original knee bone was. However, the evidence of Lucy’s pelvis was contradictory to the evidence of her knee joint. Although her knee joint locked straight, her pelvis was more similar to that of an ape.
This indicated that there was a possibility that Lucy could have not walked like a modern human. Johanson, once again turned for Owen Lovejoy advice.Lovejoy observed the unusual way the pelvis fossilize, and concluded that after Lucy’s death, her bones must have been crushed to pieces and caused her pelvis bone to fit together in a position that made it anatomically impossible. Lovejoy decided to reconstruct the pelvis to the original shaped. Using a plaster model instead of the original hip, Lovejoy put the pieces of Lucy’s pelvis together until they fit perfectly. Finally Lucy’s hip looked like that of humans, contributing additional support of Dr. Johanson claims.
Subsequently, there was outside corroboration of Dr. Johanson theory. Johanson also used the findings of the Leatoli footprints by Mary Leakey in 1976 to help support his claim of this biped creature. In Tanzania, Mary Leakey was on her own excavation in which she found footprints which have been covered in volcanic ash.The footprints were similar to that of a human, which also indicated that a biped human had walked this ground before.
The ash that covered the footprints, was also found to be dated as old as 3 million years, this is how old Lucy’s fossils had be dated to be. Dr. Johanson used this as future support for his case for Lucy, claiming that these footprints belonged to the same species he had found in Ethiopia. Showing that the Leatoli footprints are distinctively different from chimpanzee footprints, he also compared it to a human footprint.
“The great toe is in line with the rest of the toes. And what this has done in the human and the Laetoli print is to create an arch. And that’s a hallmark of typical modern upright locomotion, because the arch is an energy absorber.
And that’s the kind of fine tuning that you would expect in a biped that had been that way for a very long period of time”1. Dr. Johanson provided, interpretation and analysis for his methodology of finding and identifying Lucy, but there are many flaws in his evidence that Lucy was the oldest human ancestor. The several incongruities in his support, leads to a biased conclusion that Johanson had provided.
The first piece of evidence that comes in to question is the dating method. Dr. Johanson and Owen Lovejoy used the age of the volcanic ash that the bones were covered in to determine the age of the fossil. Because the layers of ash could have been shifted from one place to another, the dating technique could have been unreliable.
The next contradiction is the reconstruction of the pelvis. How can they reconstruct something that they did not have an original image of? The idea, that the hip bone did not allowed this creature to walk upright provides a an assumption that maybe the knee bone that was found a year ago and this knee bone was from two different species. The last piece of evidence that Johanson used in support of his conclusion is the Leatoli footprints. The footprints were discovered miles away from the site that Lucy was found, and the idea the two species was the same was under pure assumption.There was no other support that was provided for the connection of Lucy and these footprints. The finding of Lucy (Australopithecus afarensis), was one of science greatest discoveries. She was the most completed hominid at the time.
Her discovery is of such of great importance, providing the “missing link” that the world has been waiting. Her discovery also proved that humans walked upright before having larger brains. Her discovery also provides an insight of the discrepancies and biases of the scientific world. The argument of Lucy is one that continues to go on for researches, as information about human origins evolves.