Dr. Donald Johanson discovery of Australopithecus Afarensis in Hadar, Ethiopia and Mary Leakey’s discovery of the Laetoli footprints in Olduvai Gorge, Ethiopia proved beyond any plausible doubt that human species had evolved and Lucy was one of the species that bridged this gap between pre-humans and modern day humans. On his way, back to camp, Dr. Donald Johanson discovered a knee joint in the great rift in Hadar which was more like that of human than that of apes. Dating of the knee joint by using Potassium Argon to date samples of volcanic ash around the knee joint. In this process, the volcanic ash was blasted with Argon laser which melted the crystals of ash and gave off argon gas. The amount of argon gas given off could be extrapolated to predict the years of the knee joint. The dating process proved that it was about 3 million years. This time perfectly fit the theoretical expended time for evolution. …show more content…
Johanson’s discovery in 1974 filled up the empty gaps. He found almost half of a skeleton of Lucy. The skeleton included a skull, pelvis and a knee joint. Lucy got its name from the Beatles song, Lucy in the sky with diamonds which was playing in the camp the night of the discovery. Lucy knee joint was like the one he had found in the previous year. The knee joint locked together perfectly like a human knee. The team constructed its fossils and found out the fossil was three and half feet tall which had longer upper limbs which resembled that of apes. Thus, Lucy was still an ape which had features of a human. The features of the skull also showed more ape features of cranial arched more forward and a brain just larger than an average ape. The size of the brain was relatively small and thus it was argued that Lucy could not perform complex activities like making tools and weapons. The smaller brain yet human-like knee joint of Lucy was a controversial revelation because there was a largely accepted ideology in the scientific world that the missing link between humans and apes would be a quadruped who had a larger brain. It was a generally shared concept that larger brain was more important for the evolution of humans from apes than upright