Concept explainers
To review:
The concentrations of the hydrocarbons in the allopatric populations when the artificial selection acts like natural selections in the experiment where the allopatric species of Drosophila serrata is bred with D. birchii.
Given:
The graph given below shows the hydrocarbon concentration in the cuticle of allopatric and sympatric species of three species of Drosophila.
Introduction:
A study was conducted on the east coast of Australia, where two species of Drosophila, D. serrata and D. birchii, coexist and breed to produce hybrids. The hydrocarbon concentration in the allopatric and sympatric species was estimated to see the differences in them. The reinforcement mechanism was assumed to be the reason for such differences in the species.
Want to see the full answer?
Check out a sample textbook solutionChapter 22 Solutions
Life: The Science of Biology
- Which mode of selection is acting on the three Biston betularia populations shown? How can you tell from the data in the graph above?arrow_forwardEugene Eisen selected for increased 12-day litter weight (total weightof a litter of offspring 12 days after birth) in a population of mice . The 12-day litter weight of thepopulation steadily increased, but then leveled off after about 17generations. At generation 17, Eisen took one family of mice from theselected population and reversed the selection procedure: in this group,he selected for decreased 12-day litter weight. This group immediatelyresponded to the reversed selection: the 12-day litter weight dropped 4.8g within 1 generation and dropped 7.3 g after 5 generations. On the basisof the results of the reverse selection, what is the most likely explanationfor the leveling off of 12-day litter weight in the original population?arrow_forwardConsidering the concept of industrial melanism, what component of fitness or which components of fitness are experiencing natural selection in these populations of Biston betularia?arrow_forward
- In a natural population of Drosophila melanogaster, thealcohol dehydrogenase gene has two alleles calledF (fast) and S (slow) with frequencies of Adh-F at 0.75and Adh-S at 0.25. In a sample of 480 flies from thispopulation, how many individuals of each genotypicclass would you expect to observe under Hardy–Weinberg equilibrium?arrow_forwardIn the garden shed belonging to one of this text’s authors, stabilizing selection has occurred over the past 10 years in the house mouse, Mus musculus. Which of the following scenarios is an example of stabilizing selection? (a) Small and medium-sized mice cannot reach the seed shelf in the shed and therefore are at a disadvantage for finding food, so they do not survive and reproduce as well as large mice do.(b) Small mice cannot reach the seed shelf, and large mice are easily seen by hawks circling above. Medium-sized mice therefore survive and reproduce better than both small and large mice. (c) Small mice can easily cross the yard to the vegetable garden, and large mice can easily reach the seed shelf. Medium-sized mice have trouble with the seed shelf and are seen by hawks in the yard. Small and large mice survive and reproduce much better than medium-sized mice. (d) All of these are examples of stabilizing selection. (e) None of these are examples of stabilizing selection.arrow_forwardSuppose that the probability of survival of the three different types of diploid individuals in mosquitoes, as a result of the drug, is given by the constants WRR, WRS, and WSS. What are the frequencies of the three different types after this differential survival?arrow_forward
- Let’s suppose that weight in a species of mammal is polygenic, andeach gene exists as a heavy and light allele. If the allele frequenciesin the population are equal for both types of alleles (i.e., 50%heavy alleles and 50% light alleles), what percentage of individualswill be homozygous for the light alleles in all of the genesaffecting this trait, if the trait was determined by the followingnumber of genes?A. TwoB. ThreeC. Fourarrow_forwardIn a real habitat, new squirrels often come into the habitat (immigrate) and others leave the area (emigrate). How might emigration of squirrels with gray fur from this population affect the gene frequency of G and g in this population of squirrels? How might immigration of leucistic squirrels into this population affect the gene frequency of G and g in this population of squirrels? How might you simulate the effect of each of these scenarios if you were to repeat this simulation activity?arrow_forwardEntomologists at the New York State Department of Agriculture are interested in determiningthe connection between pest insects infesting crop plants with populations of the same insectinfesting native plants in natural habitats. Long term trapping and monitoring studies haveestimated that on average 3% of the populations move between habitats (farm to natural and visversa) each generation. A new insecticide resistance allele (∆K) has begun to increase infrequency in the agricultural populations. A genotyping survey at this locus of 50 individuals ineach population has revealed the following genotype counts: K/K K/∆K ∆K/∆K Agricultural field 32 16 2 Forest 48 2 0 4a. Based on the effects of migration alone, what will the frequency of ∆K be in the forestpopulation in the next generation? 4b. If migration was acting in here without selection, what would the frequency of ΔK be in theagricultural population in the next generation? 4c. If the natural forest population was…arrow_forward
- Consider the first copy of an allele for insecticideresistance that arises by mutation in a populationof insects exposed to an insecticide. Is this mutation an adaptation? If, after some generations,we find that most of the population is resistant,is the resistance an adaptation? If we discovergenetic variation for insecticide resistance in apopulation that has had no experience of insecticides, is the variation an adaptation? If an insectpopulation is polymorphic for two alleles, eachof which confers resistance against one of twopesticides that are alternately applied, is thevariation an adaptation? Or is each of the tworesistance traits an adaptation?arrow_forwardSteven Frank and Laurence Hurst argued that a cytoplasmically inherited mutation in humans that has severe effects in males but no effect in females will not be eliminated from a population by natural selection because only females pass on mtDNA. Using this argument, explain why males with Leber hereditary optic neuropathy are more severely affected than females.arrow_forwardSuppose that in generation 0, the frequency of allele A1 in a population of armadillos is 0.4. In each generation, 10 percent of the individuals in that population are migrants from another population that has an allele frequency of 0.6. a) Calculate the frequency of A1 in each of the next two generations (generations 1 and 2). b) Is the change in allele frequency in generation 2 greater than, less than, or equal to the change in generation 1? How can you explain that answer? c) What will the allele frequency become in this population after many generations? I need all three parts with calculations asap!!arrow_forward
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education