Evolution
4th Edition
ISBN: 9781605356051
Author: Douglas Futuyma, Mark Kirkpatrick
Publisher: SINAUER
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Question
Chapter 21, Problem 2PDT
Summary Introduction
To explain: The change in the effective
Introduction: A drastic change in the size of human population has been observed over the last 100,000 years. The human population is continuously increasing and is estimated to keep on increasing.
Summary Introduction
To explain: The effect of a change in population size on the contributions of natural selection and genetic drift.
Introduction: Natural selection is a phenomenon which favors the traits that are beneficial for the survival of individual and pass on these traits to next generation, whereas genetic drift is caused due to segregation of population because of the changes in the allelic frequency.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Which statement illustrates the connection between natural selection and overreproduction of a population?
a) populations vary in their inherited traits.
b) species produce more offspring than can survive in the environment.
c) individuals with inherited traits that promote survival tend to have more surviving offspring.
d) individuals with traits that do not enhance survival cannot reproduce.
Even though Hardy and Weinburg showed that the process of random reproduction will not alter gene frequency in a population over time, in wild populations we observe that gene frequencies do change overtime so what has happened?
A) sexual selection
B) Evolution due to sexual selection
C) none of these
D) any of these
E) Evolution due to genetic drift
Starting from a single wild canine species, humans have developed hundreds of breeds of domestic dogs. Which of the following statements is supported by this observation?
1) Natural selection had not occurred very frequently in the wild dog populations.
2) There was enough heritable variation in the wild canine species to create a variety of features.
3) Heritable variation is low; otherwise the there would be more wild dog species.
4) Most of the variation in domestic dog species is a result of variation in nutrition and training.
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- According to Darwin’s model of evolution, evolution can only occur if there is some variation present among the individual members of a population. Which statement best describes the source of this variation among members of a species? A) variation exists because different individuals will have different access to food and other resources B) individuals will vary depending on geography and climate C) variation exists because not all genes will be affected D) variation among individuals may arise as a result of mutations in the genetic codearrow_forwardSuppose a very small group of birds serves as the foundation of a new population. As a result, the population is very genetically homogeneous. What phenomenon has affected this population? O a) Mutation O b) Gene flow Oc) Non-random mating O d) Genetic driftarrow_forwardAccording to Darwin’s model of evolution, evolution can only occur if there is some variation present among the individual members of a population. Which statement best describes the source of this variation among members of a species? A) individuals will vary depending on geography and climate B) variation exists because not all genes will be expressed C) variation among individuals may arise as a result of mutations in the genetic code D) variation exists because different individuals will have different access to food and other resourcesarrow_forward
- According to the Hardy-Weinberg law of equilibrium: Question 1 options: A) In absence of mutation and natural selection, the frequencies of the genotypes will remain stable because no evolutionary change takes place. B) In absence of gene flow, the frequencies of the genotypes will remain stable because no evolutionary change takes place. C) In absence of genetic drift, the frequencies of the genotypes will remain stable because no evolutionary change takes place. D) All of the above. E) None of the above.arrow_forward1.) The process in which the genetic composition of a population changes with time is known as evolution. Which of the following mechanisms is not an agent of evolutionary change? A) natural selection B) mutation C) genetic drift D) random mating 2.) Which statement below is not consistent with a population in Hardy-Weinberg equilibrium? A) Genetic drift is occuring B) Random mating is occuring. C) Population size is large. D) Migration is not occuring.arrow_forwardIf mutation introduces a new allele into a population, what will happen to the frequency of the original alleles over generations? (Assume all alleles are adaptive.) a) The mutant allele will eventually be lost from the population. O b) Frequency of the original alleles will remain the same. c) Frequency of the original alleles will decrease. d) Frequency of the original alleles will increase.arrow_forward
- Which of the following does NOT tend to promote genetic divergence between populations? a) founder effect b) gene flow c) natural selection d) reproductive isolationarrow_forwardWhich of the following promotes adaptive evolution in populations? A)High genetic diversity B)Selection pressure for an environmental factor that is changing C)Greater survival and reproduction in organisms with inherited traits D)All of the above At what rate do adaptations occur in populations? A)Adaptations occur slowly, due to very low mutation rates. B)Adaptations occur quickly, due to the ability of organisms to quickly acquire traits from their environment. C)Adaptation rates can be fast when selection pressures are strong. D)Adaptation rates are always slow, due to genetic drift. Gene flow among populations results in which impact on adaptation? A)It increases the occurrence of adaptation by introducing new genes. B)It slows the process of adaptation by introducing alleles that keep the population from being dominated by the alleles best suited for the environment. C)It increases the occurrence of adaptation by moving traits acquired…arrow_forwardConsidered synonymous with migration, the movement of alleles from one population to another is referred to as: A) genetic drift B) mutation C) natural selection D) gene flowarrow_forward
- Why do you think it is necessary for there to be variation in a population in order for evolution by natural selection to occur?arrow_forwardMechanisms for the persistence of genetic variation in a population include:i) antagonistic selection, ii) overdominance, iii) heterosis, iv) inverse-frequency-dependent selection, and v) mutation-selection balance. Describe how mutation-selection balance can act to maintain genetic variation in a population.arrow_forward9) This chart shows the beak length of a population of finches in the Galapagos. The island was faced with a five year drought that made it difficult for birds to get water. If natural selection occurs, how would you predict the bird beak lengths to change? A) Only those with shorter beaks would survive. B) The population would not really change much. C) Only those with the longest beaks would survive. D) Those with medium-long beaks would increase most. Not Gradedarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College
Concepts of Biology
Biology
ISBN:9781938168116
Author:Samantha Fowler, Rebecca Roush, James Wise
Publisher:OpenStax College
Mendelian Genetics and Punnett Squares; Author: Professor Dave Explains;https://www.youtube.com/watch?v=3f_eisNPpnc;License: Standard YouTube License, CC-BY
The Evolution of Populations: Natural Selection, Genetic Drift, and Gene Flow; Author: Professor Dave Explains;https://www.youtube.com/watch?v=SRWXEMlI0_U;License: Standard YouTube License, CC-BY