Table of Contents
Who made the neutral theory of biodiversity?
McGill, B. J. A test of the unified neutral theory of biodiversity. Nature 422, 881-885 (2003). McGill, B. J., Maurer, B. A. et al.
What are the theories of biodiversity?
Biodiversity theories can inform important conservation actions such as assessments of species richness and extinction or habitat loss and fragmentation. Popular examples of biodiversity theories are niche theory and island biogeography theory, whereas neutral theory is less known.
How neutral theory altered ideas about biodiversity?
In Hubbell’s 2001 book, The Unified Neutral Theory of Biodiversity and Biogeography, he argued that many species can occupy any given niche, and whether they hold it is ultimately driven by chance. Whole ecosystems evolve through random “ecological drift,” much as genetic drift influenced the frequency of traits.
How was the theory of island biogeography tested?
The theory of island biogeography was experimentally tested by E. O. Wilson and his student Daniel Simberloff in the mangrove islands in the Florida Keys. Species richness on several small mangroves islands were surveyed. The islands were fumigated with methyl bromide to clear their arthropod communities.
What is neutral diversity?
This means that the gene variants detected do not have any direct effect on fitness. This type of genetic variation is thus selectively neutral and tells us nothing about the adaptive or evolutionary potential of a population or a species.
What are neutral processes in ecology?
Neutral processes predicate that all species are identical in their demographic rates (birth, death, dispersal and speciation rates) and exclusion processes are completely random [6].
What does the theory of island biogeography explain?
The theory of island biogeography simply says that a larger island will have a greater number of species than a smaller island. For this theory, an island is any ecosystem that is remarkably different from the surrounding area.
What is a real world example of the theory of island biogeography?
Australia. Marsupials like the kangaroo and the wallaby are only found in Australia. If marsupials were found all over the world, then that would mean they did not come into existence by means of natural selection and the evolutionary process.
What is an example of natural selection in nature?
A classic example of natural selection at work is the origin of giraffes’ long necks. The ancestors of modern giraffes were animals similar to deer or antelope, with necks of ordinary length.
Which of the following best explains the theory of natural selection?
So, the correct answer is ‘Individuals with the most favorable traits survive and reproduce’
What is the theory of island biodiversity?
The theory of island biogeography explains that the biodiversity and number of species inhabiting an island is impacted by the island’s land size and degree of isolation. Larger, less isolated islands have higher numbers of species, while smaller, more isolated islands have lower numbers of species.
What does island biogeography theory explain?
What are the three components of the island biogeography theory?
Island biogeography is determined by three processes: immigration, evolution, and extinction. These processes are determined by the area and isolation of islands such that smaller and more isolated islands have lower numbers of species than larger and less isolated islands.
What are the 3 types of interactions in an ecosystem?
The term “symbiosis” includes a broad range of species interactions but typically refers to three major types: mutualism, commensalism and parasitism.
What is natural selection in ecology?
Natural selection is the process through which populations of living organisms adapt and change. Individuals in a population are naturally variable, meaning that they are all different in some ways. This variation means that some individuals have traits better suited to the environment than others.
What is the neutral theory of biodiversity and biogeography?
A decade has now passed since Hubbell published The Unified Neutral Theory of Biodiversity and Biogeography. Neutral theory highlights the importance of dispersal limitation, speciation and ecological drift in the natural world and provides quantitative null models for assessing the role of adaptati …
Is biodiversity controlled by neutral drift?
Recent theory suggests that biodiversity is controlled predominantly by neutral drift of species abundances 1, 2, 3, 4. This theory has generated considerable controversy 5, 6, 7, 8, 9, 10, 11, 12, because it claims that many mechanisms that have long been studied by ecologists (such as niches) have little involvement in structuring communities.
What is the UNTB theory of evolution?
The UNTB predicts that the species diversity and relative abundances of species can be explained by the neutral drift of the abundances of different species, in direct analogy to the neutral theory of molecular evolution 24.
What does neutrality mean in ecology?
Neutrality means that at a given trophic level in a food web, species are equivalent in birth rates, death rates, dispersal rates and speciation rates, when measured on a per-capita basis. This can be considered a null hypothesis to niche theory.