Is Lucy The Missing Link? R Essay, Research Paper
Australopithecus afarensis, or Lucy as also know, was discovered in November 1974. She was the most complete hominid skeleton that had been found in the world at that time. Being the only complete skeleton that had been found that was older than Neanderthal, she was a great discovery, particularly as she had many distinctive features putting her in a class of her own. This led many scientists to believe that Lucy was and is the missing link in the evolution of mankind. There were however, a number of controversies surrounding her discovery that open many discussions and questions about where she really is what she first appeared to be.
The discovery of Lucy was made in northeast Africa, in the Hadar region of Ethiopia by scientists Maurice Taieb, Donald Johanson and their colleagues. This was one of the first discoveries of such a skeleton, and certainly the most complete skeleton of their find. She stood just under four foot tall yet was a mature female adult skeleton of around twenty-five years of age. She also possessed many ape-like characteristics such as long arms and short legs. Many of the other fossilised bones in the area that were found showed that there were many more like Lucy with many of them greater in size particularly the male of the species.
Lucy appeared to be human in many ways as she could walk up right. It can be seen, however, that A. Afarensis was a biped, meaning that they could walk upright and move on all fours, rather like modern day chimpanzees. There is strong evidence from Mary Leaky and Paul Abell that A. afarensis walked upright from a fossil footprint find. They saw that the force of the footprints was clearly ball of the foot first followed by toe push off. It has been found that A. afarensis may not have walked like modern day homo sapiens. They would have walked with a slight wobble, as the curvature of their bones would suggest. They also possessed climbing abilities as can be seen by long curved phalanges that would have been used to grip. These were just a few of the many ape-like characteristics that the creature appeared to have. Furthermore, their brains were in the same range of that of a chimpanzee.
Much debate around the discovery of A. afarensis was concerned with where its place in human genealogy was. Could Australopithecus be separated form homo habilis and whether there should be different categories of Australopithecus as there was such a broad area of discoveries. Largely increased cranial size and smaller teeth in Homo habilis indicating that there was indeed a call for a different category for A. afarensis. There was still further debate as to whether the new discovery of Lucy was indeed an Australopithecine as first believed. Already there had been a number of australopithecines identified. From earlier discoveries of A. Afarensis, initially fitted Lucy into that category. Her skeleton was similar to the earlier discoveries placing her in that group, however there were still some differences linking her back to Homo habilis.
Johanson teamed up with Tim White to study the debate that was surrounding the discovery of Lucy . Looking at both sets of fossils side by side they found a remarkable likeness. They appeared to be almost identical but were from supposedly different species. So Lucy was not like other australopithecines that had been discovered previously, and although was very similar to Homo habilis she still possessed characteristics to isolate her from that group. White and Johanson put forward, as an explanation of this, that Lucy s skeleton was indeed that of A. Afarensis. A. Afarensis was a direct descendant of Homo habilis and also a link to the other australopithecines. In other words, The missing link in human evolution.
This theory did not convince all scientists. There are many who place other types of Australopithecines as the link between Homo and Australopithecus. There is a gap in African fossil record that makes it difficult to identify and links for certain.
There have been a number of other important discoveries of remains of A. Afarensis that indicate that they were bipedal and of Homo and therefore human origin. 3.5 million year old fossils have been found at the sites of Turwel and Maka. They were fossils of wrist bones and hands. Although it is believed that A. afarensis did not have opposable thumbs, they did have enhanced finger mobility and a powerful wrist flexion, as suggested by a carpal tunnel about twice the size of modern humans. A number of fossil discoveries of many other bones indicate that A. afarensis was bipedal such as a low angle neck shaft, and bone thickness on the anterior neck surface is expanded. There are many more signs to say that this species was bipedal.
Further debate about the missing link have come in more recent times with the discovery of what is believed to be a new type of Australopithecine. In 1994 came the discovery of Australopithecus anamenis, and in 1995, Australopithecus ramidus (later renamed Ardipithecus a new genus type). Both these finds date to earlier that A. afarensis and have opened up the date as to whether or not Lucy was the missing link. A. Anamenis may prove to be more of the link that A. afarensis. They too were bipedal
Environment played an important part of the evolution of the Australopithecines. It is believe that earlier species lived in forest areas and were much like chimpanzees, climbing trees for food and shelter and walking on all fours to move around. It was thought that some of these creatures stood up due to the changing environment and disappearing forests. A. afarensis appeared to prove this wrong, as they were bipedal and living in forest areas at one time. However, the discovery of these latest fossils of A. anamenis and Ardipithecus show that there were bipedal species alive before the evolution of A. afarensis. It is also clear by observing the dentition of the early afarensis that they lived in wooded areas unlike what many scientists and researchers had originally thought.
In conclusion, Australopithecus afarensis has a great deal of importance in understanding the evolution and genealogy of humans. Through the discovery of Lucy scientists have been able to determine how the species developed and when they developed such things as the ability to walk. There have, however, been many controversies surrounding the discovery of Lucy . Many believe that she was not an Australopithecine but was the remains of Homo habilis and that the afarensis type did not actually exist. Despite pulling through this controversy and establishing the type, Lucy may now not be as important as she once was. Despite the great amount of knowledge gained through the study of A. afarensis a new type of Australopithecine has been discovered, possibly two, therefore the theories and idea that were made through Lucy s discovery may not hold the same value as they once did. Only when full research has been carried out on these new fossils and finding will the scientists take one further step towards discovering the truth of mankind and find out once and for all whether Lucy was the missing link .