Biology
12th Edition
ISBN: 9780134813448
Author: Audesirk, Teresa, Gerald, Byers, Bruce E.
Publisher: Pearson,
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Chapter 16, Problem 2AC
By the 1940s, the whooping crane population had been reduced to only 15 individuals. Thanks to conservation measures, its numbers are now Increasing. What special evolutionary problems do whooping cranes face now that they have passed through a population bottleneck?
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The red wolf (Canis rufus) was once widespread in the southeastern United States but was declared to be extinct in the wild. Biologists bred captive red wolf individuals and reintroduced them into areas of eastern North Carolina, where they are federally protected as endangered species. The current wild population is estimated to be about 100 individuals. However, a new threat to red wolves has arisen: hybridization with coyotes (Canis latrans), which have become more numerous in the areas inhabited by red wolves. Although red wolves and coyotes differ in morphology and DNA, they are capable of interbreeding and producing fertile offspring. Social behavior is the main reproductive barrier between the species and is more easily overcome when same-species mates are rare. For this reason, some people think that the endangered status of the red wolf should be withdrawn and resources should not be spent to protect what is not a “pure” species. Do you agree? Why or why not?
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Chapter 16 Solutions
Biology
Ch. 16.1 - define evolution in terms of concepts from...Ch. 16.1 - define equilibrium population and describe the...Ch. 16.2 - If it were true that mutations do occur in...Ch. 16.2 - Explain how the distribution of genotypes in...Ch. 16.2 - A flu vaccination stimulates your immune system to...Ch. 16.2 - Prob. 3TCCh. 16.2 - If a population grows large again after a...Ch. 16.2 - Prob. 5TCCh. 16.2 - Evolution of a Menace The mutant alleles that...Ch. 16.2 - describe how mutation, gene flow, genetic drift,...
Ch. 16.3 - A team of phys clans treated four patients with...Ch. 16.3 - If we studied a population of bighorn sheep and...Ch. 16.3 - When selection is directional, is there any limit...Ch. 16.3 - describe why selection of phenotypes can affect...Ch. 16.3 - explain how competition and predation influence...Ch. 16.3 - Prob. 3CYLCh. 16.3 - compare and contrast directional selection,...Ch. 16.3 - Microbiologists have discovered that alleles...Ch. 16 - The alleles responsible for antibiotic resistance...Ch. 16 - Stabilizing selection on a trait tends to a. make...Ch. 16 - An adaptation is a. any trait that arises from a...Ch. 16 - Which of the following statements about mutations...Ch. 16 - Genetic drift occurs a. when different phenotypes...Ch. 16 - The ______ provides a simple mathematical model...Ch. 16 - Different versions of the same gene are called...Ch. 16 - An organisms ______ refers to the specific alleles...Ch. 16 - A random form of evolution is called ________....Ch. 16 - Competition is most Intense between members of...Ch. 16 - The evolutionary fitness of an organism is...Ch. 16 - What is a gene pool? How would you determine the...Ch. 16 - Define equilibrium population. Outline the...Ch. 16 - How does population size affect the likelihood of...Ch. 16 - If you measured the allele frequencies of a gene...Ch. 16 - People like to say that you cant prove a negative....Ch. 16 - Describe the three ways in which natural selection...Ch. 16 - What is sexual selection? How is sexual selection...Ch. 16 - In North America, the average height of adult...Ch. 16 - By the 1940s, the whooping crane population had...
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