Examples of invasive species in the following topics:
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- Communities are shaped by foundation species and keystone species, while invasive species disrupt the natural balance of an area.
- These include the foundation species, keystone species, and invasive species.
- One of the many recent proliferations of an invasive species concerns the growth of Asian carp populations.
- Local and national politicians have weighed in on how to solve the problem, but no one knows whether the Asian carp will ultimately be considered a nuisance, like other invasive species, such as the water hyacinth and zebra mussel, or whether it will be the destroyer of the largest freshwater fishery of the world.
- In the United States, invasive species such as (a) purple loosestrife (Lythrum salicaria) and the (b) zebra mussel (Dreissena polymorpha) threaten certain ecosystems.
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- For this reason, exotic species, also called invasive species, can threaten other species through competition for resources, predation, or disease.
- For example, invasive plants can alter the fire regimen, nutrient cycling, and hydrology in native ecosystems.
- Invasive species that are closely related to rare native species have the potential to hybridize with the native species.
- Invasive species cause competition for native species.
- Describe the impact of exotic and invasive species on native species
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- In the United States, however, Asian carp is considered to be an invasive species.
- It disrupts the structure and composition of native fish communities to the point of threatening native aquatic species.
- The aim is to develop methods of controlling the species without damaging native fish.
- Populations are dynamic entities, consisting of all of the species living within a specific area.
- They fluctuate based on a number of factors: seasonal and yearly changes in the environment, natural disasters such as forest fires and volcanic eruptions, and competition for resources between and within species.
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- In some cases a polyploid individual will have two or more complete sets of chromosomes from its own species in a condition called autopolyploidy.
- The other form of polyploidy occurs when individuals of two different species reproduce to form a viable offspring called an allopolyploid.
- The prefix "allo" means "other" (recall from allopatric); therefore, an allopolyploid occurs when gametes from two different species combine.
- It has been suggested that many polyploidization events created new species, via a gain of adaptive traits, or by sexual incompatibility with their diploid counterparts.
- An example would be the recent speciation of allopolyploid Spartina — S. anglica; the polyploid plant is so successful that it is listed as an invasive species in many regions.
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- Traditionally, ecologists have measured biodiversity, a general term for the variety of species present in the biosphere, by taking into account both the number of species and their commonness.
- The Galápagos finches are an example of a modest adaptive radiation with 15 species.
- The Nile perch was introduced in 1963, but was not a problem until the 1980s when its population began to surge by consuming cichlids, driving species after species to the point of extinction (the disappearance of a species).
- The rate of species loss today is comparable to those periods of mass extinction.
- Specifically, three human activities have a major impact: destruction of habitat, introduction of exotic invasive species, and over-harvesting.
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- Other species cannot do this.
- Remove the entire habitat within the range of a species and, unless they are one of the few species that do well in human-built environments, the species will become extinct.
- This process may be natural or unnatural, and may be caused by habitat fragmentation, geological processes, climate change, or human activities such as the introduction of invasive species or ecosystem nutrient depletion.
- It is home to one sub-species of orangutan, a species of critically endangered elephant, and the Sumatran tiger; however half of Sumatra's forest is now gone.
- (a) One sub-species of orangutan is found only in the rain forests of Borneo, while the other sub-species of orangutan is found only in the rain forests of Sumatra.
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- Speciation is an event in which a single species may branch to form two or more new species.
- Many species are similar enough that hybrid offspring are possible and may often occur in nature, but for the majority of species this rule generally holds.
- In fact, the presence in nature of hybrids between similar species suggests that they may have descended from a single interbreeding species: the speciation process may not yet be completed.
- Given the extraordinary diversity of life on the planet, there must be mechanisms for speciation: the formation of two species from one original species.
- Biologists think of speciation events as the splitting of one ancestral species into two descendant species.
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- According to this definition, one species is distinguished from another when, in nature, it is not possible for matings between individuals from each species to produce fertile offspring.
- Species' appearance can be misleading in suggesting an ability or inability to mate.
- Thus, even though hybridization may take place, the two species still remain separate.
- Populations of species share a gene pool: a collection of all the variants of genes in the species.
- Species that appear similar may not be able to reproduce.
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- Species can be difficult to define, but most biologists still feel comfortable with the concept and are able to identify and count eukaryotic species in most contexts.
- A species' future potential for adaptation depends on the genetic diversity held in the genomes of the individuals in populations that make up the species.
- A genus with very different types of species will have more genetic diversity than a genus with species that look alike and have similar ecologies.
- A recent estimate suggests that the number of identified eukaryote species, about 1.5 million species, account for less than 20 percent of the total number of eukaryote species present on the planet (8.7 million species, by one estimate) .
- In addition, the unique characteristics of each species make it potentially valuable to humans or other species on which humans depend.
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- In the United States, the Endangered Species Act (ESA) was enacted in 1973.
- More fundamentally, the approach to protecting individual species rather than entire ecosystems is inefficient as it focuses efforts on a few highly-visible and often charismatic species, perhaps at the expense of other species that go unprotected.
- The Act now lists over 800 protected species.
- Captive breeding is meant to prevent species extinction and to stabilize the population of the species so that it will not disappear.
- Detail the benefits and limitations of different human responses to climate change and species loss, such as using preserves to conserve species