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Q: Review the Hardy-Weinberg equilibrium equation. What parts of the

Review the Hardy-Weinberg equilibrium equation. What parts of the equation represent gene frequencies? What elements represent genotype frequencies and phenotype frequencies? Are genotype and phenotyp...

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Q: Why do introduced predators possibly threaten the species diversity of a community

Why do introduced predators possibly threaten the species diversity of a community such as Lake Victoria, while indigenous predators do not? Think in evolutionary timescales as you develop your answer...

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Q: Humans have been living in the tropical rain forests of the New

Humans have been living in the tropical rain forests of the New World for at least 11,000 years. During this period, disturbance by humans has been a part of these tropical rain forests. Use the inter...

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Q: The dams that have been built on many rivers often stabilize river

The dams that have been built on many rivers often stabilize river flow by increasing flows below the dam during droughts and decreasing the amount of flooding during periods of high rainfall. Using t...

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Q: All the keystone species work we have discussed in chapter 17 has

All the keystone species work we have discussed in chapter 17 has concerned the influences of animals on the structure of communities. Can other groups of organism’s act as keystones? What about paras...

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Q: Some paleontologists have proposed that overhunting caused the extinction of many large

Some paleontologists have proposed that overhunting caused the extinction of many large North American mammals at the end of the Pleistocene about 11,000 and 10,000 years ago. The hunters implicated b...

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Q: Using Tscharntke’s food web (1992) shown in figure 17.

Using Tscharntke’s food web (1992) shown in figure 17.5, predict which species would be most affected if you excluded the bird at the top of the web, Parus caeruleus. Wha...

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Q: When Power (1990) excluded predaceous fish from her river sites

When Power (1990) excluded predaceous fish from her river sites, the density of herbivorous insect larvae (chironomids) decreased. Use the food web described by Power to explain this response.

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Q: Explain how the experiments of Lubchenco (1978) showed that feeding

Explain how the experiments of Lubchenco (1978) showed that feeding preferences, population density, and competitive relations among food species all potentially contribute to the influences of “keyst...

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Q: What is a keystone species? Paine (1966, 1969)

What is a keystone species? Paine (1966, 1969) experimented with two sea stars that act as keystone species in their intertidal communities along the west coast of North America and in New Zealand. De...

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