Greyhound German shepherd Bulldog Cocker spaniel FIGURE 28.9 Some common breeds of dogs that have been obtained by selective breeding. Genes-Traits By selecting parents carrying the alleles that have a desired effect on certain quantitative traits, dog breeders have produced breeds with distinctive sets of traits. For example, the bulldog has alleles that produce short legs and a flat face. By comparison, the corresponding genes in a German shepherd have alleles that produce longer legs and a more pointy snout. All of the dogs shown in this figure carry the same kinds of genes (e.g., many genes that affect their sizes, shapes, and fur color). However, the alleles for many of these genes are different among these dogs, thereby producing breeds with strikingly different phenotypes.

Greyhound German shepherd Bulldog Cocker spaniel FIGURE 28.9 Some common breeds of dogs that have been obtained by selective breeding. Genes-Traits By selecting parents carrying the alleles that have a desired effect on certain quantitative traits, dog breeders have produced breeds with distinctive sets of traits. For example, the bulldog has alleles that produce short legs and a flat face. By comparison, the corresponding genes in a German shepherd have alleles that produce longer legs and a more pointy snout. All of the dogs shown in this figure carry the same kinds of genes (e.g., many genes that affect their sizes, shapes, and fur color). However, the alleles for many of these genes are different among these dogs, thereby producing breeds with strikingly different phenotypes.

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter19: Population Genetics And Human Evolution

Section: Chapter Questions

Problem 10QP

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