Megafauna Extinction In Australia Essay, Research Paper

Megafauna Extinction In Australia Site Name: Cuddie SpringsGeographical Position: Northwestern New South Wales Archeological Sequence and Dates: Cuddie Springs has been excavated as a beginning of Fossil bone for a really long clip, but get downing in 1990 it has besides shown cultural stuff every bit good. First it was excavated by Judith Furby, John Dodson, and Ian Prosser from the School of Geography at the University of New South Wales and so by Richard Fullager and Robert Jones of the Australian Museum.Finds and Associations: The most of import discoveries at Cuddie Springs are found in asecure stratigraphic sequence that consists of megafaunal castanetss and artefacts happening together and dated from 19 300 old ages and traveling back to at least 29 570 plus or minus 280 old ages, which is considered a minimal age for the oldest grounds of co-existence. These day of the months, done with carbon 14 dating, are considered reasonably accurate & # 8216 ; given the deficiency of grounds for rapid deposition, propinquity to the bound of carbon 14 dating, and fundamental pre intervention of charcoal. & # 8217 ; Among the deposit has been found Ochre and many rock tools, chiefly flakes, nucleuss and scrapers, most of which are made of silcrete, but besides quartzite, vitreous silica, feldspar porphyritic rock, pudding stone and chert. As clip went on, there is grounds that quartzite became less popular for tools and chert became more popular. There has besides been found grindstones with amylum residues, a likely cylcon and other artefacts with reworked borders incorporating blood and hair. Since 1992, DNA proving on the blood and hair found have taken topographic point and have been identified as Macropus colossus and Diprotodon. Interpretation: The fact that the rock tools contains DNA of nonextant megafauna clearly shows that non merely did megafauna be at the clip of human business, but that Aborigines were at least scavenging the carcases dead megafauna and perchance were taking portion in slaughtering at bay animate beings or runing them and so transporting some castanetss back to their cantonment. Because of the sum of wood coal found and the presence of fireplaces, Cuddie Springs is considered a cantonment site.Also, environmental grounds taken from Cuddie Springs shows a decreasing tree, bush and grass screen but a rise in saltbrush as the glacial upper limit approached. This grounds agrees with environmental grounds taken from Ulungra Springs, located approx. 180 kilometer to the sou’-west. Site Name: Lancefield swampGeographic Position: Southwest border of Lancefield, a little agricultural town located in VictoriaArcheological Sequences and Dates: Lancefield swamp has been excavated since the early 1970 & # 8217 ; s by Gillespie, Horton, Ladd, Macumber, Rich, Wright, and Thorne.Finds and Associations: The swamp has a 0.2 metre midst bone bed, 1.5 metres below the surface. In this bed, the castanetss of six nonextant megafaunal species were found. The day of the months on this degree are about 26 kbp, which shows that worlds co-existed with megafauna for over 7,000 old ages. Another relevant discovery at Lancefield is the climatic grounds. At about 26 kbp, Lancefield swamp changed from a period of eroding to a swamp, where bit by bit over a metre and a half of deposit accumulated. Among the megafauna nowadays are: Macropus colossus, which can impute for 90 % of the castanetss found, Protemnodon anak, Protemnodon californium. Brehus, Sthenurus occidentalis, Diprotodon, Genyornis, and Dromaius. All of which, except for Dromaius, are now nonextant. A noticeable deficiency of juveniles is found in the M. colossus castanetss. Other artefacts found at Lancefield swamp consist of a big quartzite blade, found in 1974 by P. G. Macumber, and in the contemporary surface dirts, legion artefacts of the Holocene little tool tradition are found. The dating was done chiefly by Radio-carbon dating, coming from two distinguishable samples found in different parts of the swamp old ages apart. The dating of Lancefield swamp is accepted as accurate.

Interpre

tation: Because of the quality of the dates taken from Lancefield, it appears as if humans and megafauna co-existed for over 7,000 years, raising serious doubts about the theory that humans caused the rapid extinction of megafauna in Australia due to over-hunting. Also, because the climatic evidence agrees with other southeast Australian sites in the fact that a major hydrologic change occurred at 26,000 ybp, it leads us to believe that climatic changes had more to do with the extinction than the presence of man. This is not to say that humans didn’t play a part in the extinction of megafauna, but only that they were not the soul cause, possibly not even the main cause. Evidence taken from the animal remains found at Lancefield, specifically the bones of M. titan, show evidence of signs of drought. The lack of juveniles in the bones has also been observed in modern herds during drought and many of the remains also show signs of “lumpy jaw”, a disease seen more commonly during periods of droughts. One possible theory is that the recurring droughts forced the larger species to congregeate around the sources of water, which were slowly drying. As the animals became limited in their movements due to lack of other sources of water, they became restricted to smaller and smaller areas. Then the large herds quickly ate the available sources of food and doomed themselves to extinction. A possible problem with this theory is that not all of Australia became extremely arid at this time, but research points to a large extinction of megafauna across the whole continent and not just in the parts that experienced recurring droughts.Site Name: Lake Mungo.Geographical Position: Western New South Wales.Archeological Sequence and Dates: Bowler excavated Lake Mungo in the 60’s and 70’s. Thorne removed WLH 1 from her carbonate encrustation, and he also did work with Bowler on WLH 3.Finds and Associations: Two human skeletons were found at Lake Mungo along with numerous collections of shells, hearths, ochre, and stone tools. Lake Mungo is significant because the skeletons had undergone burial rituals. WLH 1 was first cremated and then her bones were crushed, and WLH 3 was buried with ochre surrounding his body, even more remarkable since the nearest natural occurance of ochre is over 10 km away. The date for WLH 1 is approximately 25 kbp, while the date for WLH 3 appears to be around 30 kbp. No fossils of megafauna are found at this site with a date co-existing with any human remains.Interpretation: Lake Mungo relates to the extinction of megafauna in the fact that it represents a archeological find that dates back at least 30 kbp without any signs of megafauna. It is unclear if this means that the megafauna were already extinct in this area at this time or if the humans simply drove them off. We do know that Lake Mungo was a large fresh water lake that would have been an ideal habitat for many of the species referred to as megafauna, since it provided a stable water source and an abundant supply of food. Because of the lack of megafauna around Lake Mungo at the time of human occupation, it appears that humans didn’t play a part in megafauna’s extinction. If humans had massively killed the megafauna, their would be archeological sites preserving their remains, due to the high amount of calcium carbonate found around the lake shores where humans camped. Because Lake Mungo would have made an excellent habitat for megafauna as well as humans, yet megafauna is clearly lacking, we can conclude that megafauna abandoned Lake Mungo before humans occupied it. One possible theory about Lake Mungo is that the megafauna left the area in search of food before it grew into the lake it was, and the megafauna never had reason to return. Another possible reason is that as humans approached their habitat, the megafuana gradually moved on rather than compete with the new species. Either way, there is no sign of humans and megafaunas interacting in any way.