A species of hummingbird feeds on nectar of a particular plant whose flowers form a long, skinny cup. Beak length is a heritable trait that varies among individual hummingbirds. The birds' beaks must be long enough to reach the nectar, but longer beaks are also heavier and make flying more costly in terms of energy. a. Which mode of selection is this hummingbird species experiencing? b. How does this mode of selection affect the mean and standard deviation over time?

A species of hummingbird feeds on nectar of a particular plant whose flowers form a long, skinny cup. Beak length is a heritable trait that varies among individual hummingbirds. The birds' beaks must be long enough to reach the nectar, but longer beaks are also heavier and make flying more costly in terms of energy. a. Which mode of selection is this hummingbird species experiencing? b. How does this mode of selection affect the mean and standard deviation over time?

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

See similar textbooks

Similar questions

Butterflies show 3 phenotypes due to incomplete dominance at the D locus with alleles DY and DB giving green phenotype in heterozygotes and yellow and blue in homozygote. If the butterflies were subject to predation by birds that could easily detect blue & yellow individuals what effect would you expect this to have on the genotype and allele frequencies over time? Indicate possible percentages.
The response to selection of flower size in a plant species is studied. Flower size is measured in the population and an average of 30.4 mm is obtained. A set of plants with average flower size of 34.13 mm are allowed to interbreed and a their offspring have a mean flower size of 32.21 mm. What is the realized heritability? A. 0.485 B. 0.846 C. 0.767 D. 0.979
Scientists study the possible effects of human activity on the genetic variations within members of two populations of sparrows, A and B, that live within similar ecosystems. Population A lives in a recreational campsite while population B lives in a nature preserve. Both populations exhibit similar genetic variation between the parent population and second generation. However, a tornado touches down in the habitat of population A during the lifespan of the second generation. Which statement best describes the predicted difference between the third generation of the two populations? A - Population B underwent a speciation that will lead to an increase in the genetic variation of the third generation compared to population A due to natural selection. B - Population A underwent a speciation that will lead to an increase in the genetic variation of the third generation compared to population B due to natural selection. C - Population B underwent a bottleneck effect that will lead to a…
You decide to examine call duration in Canadian toads at Big Lake near Edmonton. Call duration in the toads is determined by a single autosomal locus "noisy", at which there are two alleles (N & n). You observe three distinct call patterns in the toad population: Long duration, intermediate duration and short duration calls. Based on research from Dr. Phoney Balloni longer calling is dominant to short duration. On one evening at Big Lake you and your socially distanced assistants record the phenotypes of the toads in the table below. Phenotype No. of individuals Long 123 Intermediate 226 Short 101 Determine whether the population is in Hardy-Weinberg equilibrium. a) What are the frequencies of N and n?. b) What are the expected frequencies for each phenotype? c) Is the population is in HW equilibrium?
Assume you are studying a trait that affects boldness in blackbirds. You discover that boldness is a quantitative trait with many loci affecting the phenotypic value of the trait. Given that you know it's a phenotypic trait, is any single QTL likely to have a strong effect on the phenotypic value of the trait? a. Yes b. No c. It depends on the environment d. Not enough information to tell
A different locus codes for drought tolerance in desert tortoises. On average during a drought, genotype AA produces 7 offspring, genotype AB produces 8 offspring, and genotype BB produces 3 offspring. The genotype frequencies in 2019 are 10% AA, 10% AB, and 80% BB. What is the expected equilibrium allele frequency p* after a large number of generations go by during the drought? Assume the tortoise population is also very large.
You are examining population genetics of aquatic iguanas that live on the Galapagos islands. When you go to visit, you notice that the iguanas can easily swim to close neighboring islands but would have swim very long distances to reach further islands. Which of the following statements is a likely conclusion from your research? a. Populations are less similar the closer the islands are to each other. b. The further the islands likely have the greatest genetic diversity. c. Larger islands always have the lowest heterozygosity. d. Smaller populations on very small islands exhibit greater population differentiation.
If a population is experiencing directional selection with respect to wing color, what type of selection would you expect it to experience with respect to antenna length?
In a population of pika, you find that individuals vary in their fur color - there are greyish and black pikas. The genetic mechanism behind fur color is mainly regulated by one gene Attractie, and in this population there are only two alleles for the Attractie gene: A1 and A2. Greyish fur color is better camouflaged when they inhabit in talus (broken rocks); black fur helps protect them against predators in coniferous forests, where pika makes burrows under fallen logs and tree stumps. Why might you hypothesize that this pika population is not in Hardy-Weinberg equilibrium? What do you think is happening? Clearly explain your reasoning.
What is inbreeding depression? Why do self – pollinated crops do not show the ill- effects of inbreeding depression?
When calculating heritability in finch beak size using parent/offspring data, we find that 70 percent of the variation in the trait is due to genetics. What might explain the remainder of the variation? Select all that apply. A. nutrition B. color C. precipitation D. stress E. rarity F. temperature
Average human height has changed over the past few centuries. The current generation's average height is 168 centimeters (i.e. 5 foot 10 in). The selection coefficient for height is ß = 0.08, phenotypic variation is Vp = 1.5, and heritability is h² = 0.45. = a. What is the response to selection (R) for height? b. What is the average height expected to be for the next generation? c. Would you say this is strong or weak selection?