In the nineteenth century North American bison populations were reduced to near extinction for a variety of reasons, all of which are human-related and a result of settler activity in the region. bison population has undergone wide fluctuations in size throughout history; however, human activity, including using bison as a food source, introduction of animal species that competed for habitat, and hunting, all dramatically reduced herd populations.
Early North American settlers and Native American Indians relied on bison as a food source. nomadic hunters would follow herd movements across the plains and to the Rocky Mountains where bison grazing trails had been established. it is estimated that 20 to 30 million bison once dominated the North American landscape and it was in part this gigantic population that led many people to believe that bison was an inexhaustible and limitless supply of food. as the settlers moved west, over-consumption of the bison reduced bison populations to less than 2,000 before the turn of the nineteenth century.
During the American Civil War period, humans introduced many other grazing species that directly competed with bison for habitat and food resources. these species included cattle and horses which forced bison into smaller and smaller pockets of habitat. this had the result of bison directly competing with each other for food. under these circumstances, it is no wonder bison populations were quickly decimated.
Technological developments in the accuracy and range of rifles also had a considerable impact on bison herd populations. the new rifles allowed for increased accuracy from increased distances so that the slaughter of bison became easier and easier. the increased mortality of these new rifles, coupled with the fact that many people took up bison hunting for sport, pushed bison to the brink of complete annihilation.
Summarize the points made in the lecture you just heard, explaining how they cast doubt on the specific theories discussed in the reading passage.
The reading material explains that
North American bison populations were reduced to near-extinction due to
human-related factors such as overconsumption, introduction of competing
grazing species, and hunting. However, the listening material casts doubt on
this theory by providing evidence that suggests otherwise.
Firstly, the reading material points
out that the westward movement of early North American settlers who relied on
bison as a food source may be the primary cause of the reduction in bison
populations. In contrast, the professor asserts that historical records show a
geographic reduction in bison herd numbers starting in the west, rather than a
decrease in bison populations from east to west.
Furthermore, the reading material
suggests that cattle and horses were introduced and forced bison out of their
natural habitats. However, the lecturer challenges this theory by pointing out
that bison are tough and aggressive animals that can compete with other grazing
species for food. Additionally, bison are adapted to survive in cold and
mountainous regions that cows and horses may find unsuitable for living and
grazing.
Lastly, the reading material mentions
that advancements in rifle technology had a considerable impact on bison
populations. However, the listening material disputes this theory by stating
that similar large game animals in other parts of the world did not experience
population declines following the introduction of new gun technology. This
implies that rifle improvements may not have been the sole or primary cause of
the reduction in bison populations.
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