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What is a species? What exactly is an endangered species? What is an extinct species? How have these species come to the point of becoming endangered or extinct? What can we do to save the endangered species that are near extinction? Can we actually do anything to save these species, or is it a lost cause? Why should I care?
The answer to many of these questions is not know by most people. As much attention as this subject gets from environmental groups and agencies, it gets just as much ignoring by the general public. Many people feel compelled to help or contribute, yet few seldom do carry out their intentions. This is a very serious subject that needs to receive immediate and full attention from the general public. Only they can truly make a difference. The concept of extinction just doesnt seem to be fully understood by many people. Once theyre gone, theyre gone for good. There is no returning from extinction. If we continue at the present rate we are at now, we could lose one bird or mammal species per year by the year 2000. These concepts and questions will be fully answered by the time you have completed reading this paper,
According to The American Heritage Dictionary of The English Language, A species is a fundamental category of taxonomic classification, ranking after a genus, and consisting of organisms capable of interbreeding . A simpler working definition agreed upon by most biologist is if two visibly different though similar groups of organisms live together with little or no sign of interbreeding, they are considered to be separate species. Dogs, cats, trees, flowers, and humans are all different examples of species. A definition of endangered species and a classification of when a species is endangered is such, organisms once common and abundant but now rare in numbers in the wild are considered to be endangered. And obviously, species that do not exist anymore are considered extinct. These are important fundamental concepts that need to be understood before anything can actually be done to help save or prevent endangered species from becoming extinct.
What is an endangered species?
Endangered species are those considered to be at risk of extinction, meaning that there are so few left of their kind that they could disappear from the planet altogether. Endangered species are threatened by factors such as habitat loss, hunting, disease and climate change, and usually, endangered species, have a declining population or a very limited range.
The current rate of extinction is thought to be far greater than the expected natural rate, with many species going extinct before they have even been discovered. Shockingly, current estimates suggest that a third of the world’s amphibians, a quarter of all mammals and one in eight birds are endangered.
Endangered species usually have a small or declining population size or a very limited range, meaning factors such as habitat loss, hunting, disease or climate change could cause them to disappear completely within our lifetimes.
Why are species endangered?
Animals and plants face a large number of different threats with many of them being a direct result of human activity. Some of the most common threats include:
1. Habitat loss and habitat fragmentation - The ever expanding human population constantly requires additional space and resources. Land is being cleared to harvest products such as timber as well as to make way for human settlement, agriculture and transport links.
2. Hunting and poaching - A wide variety of animals have been hunted, or fished, beyond sustainable levels and now face possible extinction. Species, such as the tiger, are often hunted because they provide a resource such as food or parts which are used in traditional ‘medicine’. However, some species, such as the cheetah, have been persecuted after gaining a negative reputation for feeding upon livestock or crops or posing a threat to human safety.
3. Invasive species - Humans have introduced non-native species (both intentionally and accidentally) to a wide variety of habitats, often with devastating consequences. Introduced species may prove highly adaptable and outcompete native species for resources. Introduced predators can decimate local species which are not adapted to avoid predation, for example ground dwelling birds like the kakapo.
4. Climate change - Droughts, ocean acidification, the loss of sea ice and an increase in storms and extreme weather events can all threaten species’ survival. Sedentary species like plants or specialist species which inhabit small ranges or islands, or those with specific habitat requirements are particularly vulnerable.
5. Disease - Small populations, especially those which are limited in terms of genetic diversity are particularly vulnerable to disease. Disease can often be spread by domestic animals or accidentally introduced by humans travelling from an affected area to one which had not previously been exposed.
6. Collection / pet trade - Many animals and plants, such as the Venus flytrap, have been collected from the wild beyond sustainable levels to be sold through the pet trade or be kept in private horticultural collections.
7. Pollution - Acid rain, heavy metals, pesticides, plastic waste and oil spills all harm the environment and put species at risk. Chemicals are particularly harmful to species that live in water.
The methods and causes of many species becoming endangered and extinct are many and varied. Yet they are all related and caused by one all important underlying factor, humans. Humans are responsible for nearly every endangered species being that way and for very many of the species that have become extinct within the past few hundred years. The main reason for a species becoming endangered is the loss of natural habitats. Each year thousands of acres of rainforests are cut down or deforested, wetlands and marshes are drained, and slowly but surely the grasslands are being replaced by cities, towns, and highways . This is a world wide problem. When a species natural habitat is destroyed or reduced, there is basically nowhere to go. A displaced species of a destroyed or severely polluted habitat often times cannot adapt fast enough or well enough to survive. A species in a reduced habitat often times has to fight just to stay alive. The reduction causes an increase in the population density of not only that particular species, but every other species in that habitat as well . With higher population densities, resources such as food, water, and nesting places become so sparse that they cannot possibly support the demand. This leads to the endangerment of hundreds of species worldwide. Many of the already extinct species went through this exact process of their demise.
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