Introduction (403/400 words)
Although humans have contributed largely to the evolution of the world in a positive way, they have also deteriorated the world specifically through the abundance of fossil fuels used. Said fossil fuels have contributed to many downfalls regarding our planet, one principal problem being global warming. In this essay, I will endeavour to obtain a potential resolution to the continuous debate that is ‘Did humans cause megafauna to become extinct?’. The first possible way humans may have been responsible for the overall extinction of megafauna is through overkill, this is the hypothesis that humans drove many species of megafauna to extinction through excessive hunting. The following and more natural process that megafauna may have become extinct is through climate change this is the hypothesis that substantial fluctuations in the climate caused habitats to reduce in size, leaving megafauna with no food source or shelter.The last way megafauna may have become extinct is through disease. The megafauna in this essay all existed during the Pleistocene however now as we are in the Holocene Some animals that existed throughout the Pleistocene include Sabertooth cats, mammoths, mastodons, and giant ground sloths. All of this listed megafauna and much more became extinct throughout the Quaternary extinction event. Mammoths or Mammuthus proboscideans are possibly the most famous mammal to become extinct during the Pleistocene. Mammoths proboscideans lived approximately 5 million years ago until 4,500 years ago. Although there is no direct answer to why these mammals became extinct, there are various factors that could and will have contributed to the overall extinction of mammoths. Hyper-disease, overkill, and climate change are all large factors that may influence us to a possible resolution to the end of end-Pleistocene extinction.
The Pleistocene, frequently attributed to as the ice age, is the epoch that began about 2,588,000 million years ago and persisted until approximately 11,700 years ago. The Pleistocene period saw the extinction of various species of megafauna, which resulted in a depopulation of faunal density. Although no one is completely sure if only one of these causes leads to numerous extinctions, throughout this essay i will explain the possible cause and provide evidence that will persuade us wether the chosen category is responsible for many extinctions. The categories listed below are all hypotheses and contain both sources and evidence to support their arguments throughout this essay their reliability will be tested as we look for a possible conclusion.
Many believe that overkill is the primary reason many megafauna became extinct during the Quaternary period. The overkill hypothesis is the argument that the Genus homo is liable for the extinction of late Pleistocene megafauna. The hypothesis could explain why megafauna experienced extinction, as humans chose larger mammals to hunt as they provided the most food.
The hypothesis originally presented by Palaeontologist Paul s Martin of the University of Arizona declares that, the time of extinction corresponds to the time when Genus homo had first settled in America (approximately 14,00 years ago), thus the Genus homo must be liable for the extinction. This statement is supported by the fact that the aforementioned megafauna were co-existing with humans in Africa.
Therefore the large mammals had developed anti-predator behaviours against humans in order to protect themselves.7, as there were no other predators for the mammals, the rapid decline in population is unexplained. However large burials were found to contain large remains of megafauna, this explains that the Africans must have developed a way to kill the megafauna
In conclusion i believe that overkill may be the possible reason why megafauna faced extinction. This hypothesis is very reliable as humans today still kill many animals as a food source therefore it is easy to believe that approximately 20 thousand years ago humans were also doing the same thing
Climate change (241/400)
The climatic hypothesis suggests that substantial fluctuations in the earth’s climate are primarily responsible for the extinction of many megafauna.
Approximately 20 thousand years ago, after the end of maximum glaciation, significant
environmental changes took place as the climate warmed. These changes led to land becoming extinct. The mammoth steppes or the steppe-tundra was a large grassland biome that was home to many variations of megafauna, the grassland was the earth’s most extensive biome during the last glacial maximum2. Spanning from Spain to Canada, losing the land had a prominent effect on the megafauna population. Thereupon, the extensive land was repossessed by dense, wet forestry (opposite to the original landscape) which was unsuitable for the megafauna. The rapid decline in habitat consequently lead to the extinctions of numerous megafauna 3 as they are large mammals and require a commensurate amount land. The megafauna instantly felt the pressures of climate change rapidly whereas the smaller animals which were insensitive to environmental and climatic changes, and only began to feel the large changes after the decline in megafauna.4
The timing of the last glacial interval, which occurred from the end of the Eemian interglacial to the end of the Younger Dryas, was similar to the time that the last glacial interval ended, between 10,000 and 12,000 years ago. 8
Conversely, some argue that the last glacial interval was only one of about 20 that occurred during the Pleistocene Epoch.5
After considering the evidence presented above I do not believe that the climate change hypothesis alone is not liable for the extinction of all end-pleistocene megafauna. I have came to this conclusion based on the fact that the extinction of the mammoth-steppes could not have killed the whole megafauna population, although it can be argued that it is highly likely that it was reliable for the death of the majority of the population.
Are we close to a conclusion and solution
In conclusion to the categories presented above I, personally believe that although these problems may have lead to the extinction of masses of megafauna however, not one singular xxx could have been the cause for extinction alone. Moreover, I do believe that a combination of all of these factors may have resulted in the extinction of mammals such as the Panthera leo. For example although overkill may not have been singularly responsible it is, indeed highly likely that a combination of both overkill and climate change is liable for wiping out the megafauna population thousands of years ago. For this reason alone i believe that we may never come to a conclusion to the presented question that is ‘what killed all the mammoths and megafauna?’. As for ‘Are we close to a solution for the causes of end-pleistocene extinction?’ i believe we are not as for the same reasons presented above. Lastly, after considering the evidence i do believe that humans are partly responsible for the extinctions as they undoubtedly killed masses of megafauna, however this leads me to the question ‘would humans have survived without the megafauna?’ although extinction is regarded as a negative xxx I personally believe without killing the animals the few humans that were on the earth may not have survived through the centuries overall resulting in no life today, and then what would the world be like? would it have been abandoned and wasted? Or would it have been a paradise of animals?