BIOLOGY
12th Edition
ISBN: 9781260169614
Author: Raven
Publisher: RENT MCG
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Textbook Question
Chapter 20, Problem 2S
On large, black lava flows in the deserts of the southwestern United States, populations of many types of animals are composed primarily of black individuals. By contrast, on small lava flows, populations often have a relatively high proportion of light-colored individuals. How can you explain this difference?
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You are surveying of the turtle species identifies several breeding populations in different habitats across the island. After a very warm summer of 2020, you observe that the hatchlings from low-elevation nests are mostly males, whereas hatchlings from higher elevations have an equal female-to-male sex ratio. As a bit more background, temperature influences the sex ratio in some turtle species, a phenomenon called temperature-sex determination (TSD). With this knowledge, you hypothesize this new turtle species exhibits TSD, and that eggs incubated at low elevations during the warm year experienced a high enough embryonic temperature to skew the sex ratio. To test this, you collect 20 newly laid eggs in early 2021 & take them back to the lab to conduct an experiment to test your hypothesis that this species exhibits TSD. Assume you know the average nest temperature in the wild, and you have access to multiple incubators
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Two closely-related species overlap at the southern edge of the range for species A, and the northern edge of the range for species B. Both species consume the same prey, but differ in their preferred prey size. Researchers collected individuals from the part of each species’ range where they do not overlap. They compared the consumption of prey across a range of prey sizes for these individuals in experiments where they were grown alone (solid lines) and compared this to when the species were grown together (dashed lines). Their results are in the attached figure.
Part a
How does the mean size of prey consumed change for species A when together?
a) increase
b) decrease
c) stay the same
Part B
How does the range of prey sizes consumed change for species B when together with species A?
a) Increase
b) decrease
c) stay the same
Part C
Which species is the stronger competitor? Why?
Chapter 20 Solutions
BIOLOGY
Ch. 20.1 - Define evolution and population genetics.Ch. 20.1 - Prob. 2LOCh. 20.2 - Explain the HardyWeinberg principle.Ch. 20.2 - Describe the characteristics of a population that...Ch. 20.2 - Prob. 3LOCh. 20.3 - Define the five processes that can cause...Ch. 20.3 - Prob. 2LOCh. 20.4 - Prob. 1LOCh. 20.4 - Prob. 2LOCh. 20.4 - Demonstrate how the success of different...
Ch. 20.5 - Prob. 1LOCh. 20.5 - Prob. 2LOCh. 20.5 - Prob. 3LOCh. 20.6 - Define frequency-dependent selection, oscillating...Ch. 20.6 - Prob. 2LOCh. 20.7 - Define and contrast disruptive, directional, and...Ch. 20.7 - Prob. 2LOCh. 20.8 - Explain how experiments can be used to test...Ch. 20.9 - Prob. 1LOCh. 20.9 - Prob. 2LOCh. 20.10 - Prob. 2LOCh. 20 - If all white cats died, what proportion of the...Ch. 20 - Assuming that the values on the x-axis represent...Ch. 20 - Prob. 3DACh. 20 - Prob. 4DACh. 20 - Examine the index of copper tolerance on nonmine...Ch. 20 - Prob. 6DACh. 20 - Why are rare alleles particularly likely to be...Ch. 20 - Prob. 2IQCh. 20 - Prob. 3IQCh. 20 - Prob. 4IQCh. 20 - Prob. 5IQCh. 20 - Prob. 6IQCh. 20 - Prob. 7IQCh. 20 - Prob. 8IQCh. 20 - Prob. 9IQCh. 20 - Assortative mating a. affects genotype frequencies...Ch. 20 - When the environment changes from year to year and...Ch. 20 - Many factors can limit the ability of natural...Ch. 20 - Stabilizing selection differs from directional...Ch. 20 - Founder effects and bottlenecks are a. expected...Ch. 20 - Relative fitness a. refers to the survival rate of...Ch. 20 - For natural selection to result in evolutionary...Ch. 20 - Prob. 8UCh. 20 - In a population of red (dominant allele) or white...Ch. 20 - Genetic drift and natural selection can both lead...Ch. 20 - Prob. 3ACh. 20 - Prob. 4ACh. 20 - In Trinidadian guppies a combination of elegant...Ch. 20 - On large, black lava flows in the deserts of the...Ch. 20 - Based on a consideration of how strong artificial...
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