Tiny foxes live on the Channel Islands off the coastof Southern California; the adults weigh less than3 lbs. These so-called island foxes (Urocyon littoralis) derived from the mainland gray fox (Urocyoncinereoargenteus). Analysis of genome sequencesrevealed that unlike the mainland foxes, the foxeson a single island have shockingly little geneticdiversity.a. The genome of only one fox from each island wassequenced. How would the lack of genetic diversitybe evident in a single genome sequence?b. The populations of the foxes on each island aresmall. How might the low diversity have occurred?c. Why is low genetic diversity thought to lead tospecies extinction?d. Hypothesize as to why the Channel Island foxesare thriving without human assistance despite theirlack of genome sequence diversity

Tiny foxes live on the Channel Islands off the coastof Southern California; the adults weigh less than3 lbs. These so-called island foxes (Urocyon littoralis) derived from the mainland gray fox (Urocyoncinereoargenteus). Analysis of genome sequencesrevealed that unlike the mainland foxes, the foxeson a single island have shockingly little geneticdiversity.a. The genome of only one fox from each island wassequenced. How would the lack of genetic diversitybe evident in a single genome sequence?b. The populations of the foxes on each island aresmall. How might the low diversity have occurred?c. Why is low genetic diversity thought to lead tospecies extinction?d. Hypothesize as to why the Channel Island foxesare thriving without human assistance despite theirlack of genome sequence diversity

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter19: Population Genetics And Human Evolution

Section19.8: Genomics And Human Evolution

Problem 2GR

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In a study of a muscle disorder, several affected families exhibited vision problems, muscle weakness, and deafness (M. Zeviani et al. 1990. American Journal of Human Genetics 47:904–914). Analysis of the mtDNA from affected members of these families revealed that large numbers of their mtDNA molecules possessed deletions of varying lengths. Different members of the same family and even different mitochondria from the same person possessed deletions of different sizes, so the underlying defect appeared to be a tendency for the mtDNA of affected persons to have deletions. A pedigree of one of the families studied is shown below. The researchers concluded that this disorder is inherited as an autosomal dominant trait, and they mapped the diseasecausing gene to a position on chromosome 10 in the nucleus. Q. What characteristics of the pedigree rule out inheritance of a trait encoded by a gene in the mtDNA as the cause of this disorder?