Humans’ Affect on Extinction
If extinction is a natural part of the world, why should we worry about it? Speciation results in new species filling the ecological niche of extinct species. Why should we care if we speed up this process? Biologists say there are four main reasons to care about extinctions. First, the world’s species are a vital part of the earth’s life support system. A second reason is that species usually contribute to economic services. The third reason is that it takes 25-50 times longer for speciation to occur than extinction. Finally, we have a moral obligation to protect species’ right to live. So how are humans accelerating species extinction? The main causes of extinction due to humans are HIPPCO: Habitat destruction, degradation, and fragmentation; Invasive species; Population growth and increasing use of resources; Pollution; Climate change; and Overexploitation. The biggest threat to wild species is habitat loss, degradation, and fragmentation. A perfect example of this is the loss of habitat for the polar bears. Because of global warming, there have been less floating ice sheets in the arctic. The ice sheets are vital for the polar bears. We have seen a sharp decline in polar bear populations due to this loss of habitat. The next biggest threat to animals is invasive species. Most introduced species are very good. Corn and wheat feed most of the United States. Unfortunately, introduced species may have no common predators, competitors, diseases, or parasites. These species can overrun an ecosystems and destroy its balance. For example, a giant African land snail was introduced to Brazil in 1988. These snails were used as a cheap substitute for escargot, but were released into the wild after its price dropped. These snails now inhabit 23 of Brazil’s states and devastate the crops and native plants of the country. Population growth, overconsumption, pollution, and climate change can cause species extinctions. Growth of the...
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