Life: The Science of Biology
11th Edition
ISBN: 9781319010164
Author: David E. Sadava, David M. Hillis, H. Craig Heller, Sally D. Hacker
Publisher: W. H. Freeman
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 20.4, Problem 2R
Summary Introduction
To review:
The reason behind considering the human birth weight to be stabilizing rather than directional.
Introduction:
The natural selection is the process by which the organism adapts to the existing environment in order to have a better chance of survival. The natural selection follows three types of selection patterns depending on the circumstances. These are stabilizing, directional, and disruptive. In the stabilizing population, an average phenotype is promoted and in the disruptive selection, the extreme
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
What is meant by "relative fitness"?
In improving single trait in swine, which of the following will you expect to have the highest response to selection?
Marbling
Birth weight
Average daily gain
Litter size
The absolute fitnesses of the three genotypes in a two-allele system are given as follows:
Genotype Absolute Fitness
AA
0.08654
Aa
0.32143
aa
0.01662
What is the strength of selection against (i.e., the selection coefficient of) the Aa genotype?
(Numerical answer; please do you all your work with at least 5 digits of precision)
Chapter 20 Solutions
Life: The Science of Biology
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
- Imagine that you’re studying a species of bird. Let’s say the House Sparrow. You are interested in whether the species exhibits personality and whether there is selection on personality traits. Design an observational and experimental study to determine whether House Sparrows have a personality and, separately, design a study that would test the idea that there is currently selection on this trait(s)arrow_forwardYou are studying the heritability of maze running ability in rats. You test parents and their offspring in the maze and give them a score. ponitel Odepositphotos You produce the following graph: A 4 2 slope = = 0.9 8 -10 - 12 -10 -8 -9- -4 -2 0 2 4 6 8 midparent maze score offspring maze scorearrow_forwardWe have learned that the response to selection is equal to the selection differential times the narrow-sense heritability, and that the narrowsense heritability includes only the additive genetic variance. Why aren’t the dominance genetic variance and the gene interaction variance included? Why don’t they contribute to the genetic variation that is acted on by selection?arrow_forward
- Write the survivor rate for AA and Aa genotypes (write the answer in decimal numbers, not in fractions) Survivor rate of AA= Survivor rate of Aa= Write the absolute fitness for AA and Aa genotypes (write the answer including two decimal figures) Absolute fitness (W) of AA= Absolute fitness (W) of Aa= Write the relative fitness for AA and Aa genotypes (write the answer in decimal numbers, include two decimal figures) Relative fitness (w) of AA= Relative fitness (w) of Aa= asap please.arrow_forwardWhich type of selection (directional, disruptive, stabilizing) changes the overall average phenotype in a population? How does it do this? What does "additive” mean? Why aren't dominant and epistatic variances considered to be additive?arrow_forwardCerebellar abiotrophy (CA) is a recessive, genetic neurological disease found in the Arabian horse breed. If the incidence of this disease is about 1 in 400 Arabian horses, estimate the frequency of carriers in a population in Hardy-Weinberg equilibrium. Value of q²: 0.0025 Value of q: 0.05 Value of p: 0.95 Carrier Frequency: 0.095 How many horses would you expect to be carriers for cerebellar abiotrophy if the population consists of 582 Arabian horses? (Round to the nearest whole number and enter 2 digits.)arrow_forward
- So how do we actually decide whether the difference is large enough? We use statistical tests to calculate a p-value (probability) for the difference between the two groups we are comparing. In the beetle food preference experiment from above, it was found that beetles spend longer times with food #1 compared to food #2, and the p value for this difference was calculated to be 0.9. What does a p value of 0.9 mean here? There's a 9 (nine) % chance that the difference is due to actual beetle preference of food #1 over food #2. There's a 90% chance that the difference is due to chance, and not actual beetle preference of food #1 over food #2. There's a 90% chance that the difference is due to actual beetle preference of food #1 over food #2. There's a 9 (nine) % chance that the difference is due to chance, and not actual beetle preference of food #1 over food #2.arrow_forwardAn early study found that postal workers who worked in the office had higher rates of coronary heart disease than those who delivered mail on foot. The investigators concluded that physical activity is inversely related to risk of developing coronary heart disease. Sceptics disagreed, pointing out that the postal clerks were older than the postal carriers, and that age is a risk factor for coronary heart disease. This argument highlights the possible role of: -Chance? -Selection bias? -Recall bias? -Confounding?arrow_forwardYou observe some bark beetles with different feeding behaviors. You find that the behavioral phenotypes you observed are closely associated with the following genotypes. genotype phenotype number observed BB feeds under bark 60 Bb feeds on top of bark 24 bb feeds on leaves 16 a) What are the allele frequencies and the expected number (out of 100 beetles) of genotypes? b) Calculate the Chi-Squared value (c2). Then look up the p-value using this Chi-squared calculator: https://www.mathsisfun.com/data//chi-square-calculator.html Enter “1” for Degrees of Freedom. (There are 3 genotype categories, but only 1 DF because they are not fully independent—calculated from just 2 allele frequencies). The p-value is the probability that you would see the deviance you observed by chance, assuming the null hypothesis is true). Report both values. Is the population in H-W equilibrium? c) If you answered “No” to b): Provide at least three biologically…arrow_forward
- A biologist set up an experiment to study 3 lizards. On the first day of his study, he measured the mass of the three spice mens. He made sure that all lizards weigh 100 grams. Then the lizards were put into individual cages with the following conditions. 1. What is the independent variable? 2. What is the dependent variable? 3. Which among the set ups is the control set up? 4. Which of the item is/are the experimental set ups? 5. Based on the result of the experiment, what conclusions can be drawn from this?arrow_forwardStorage of excess carbohydrates in the diet in the form of fat would have helped human populations survive famine. However, this process is also a risk factor for obesity and type 2 diabetes in modern populations. Modern populations vary greatly in the prevalence of type 2 diabetes, but there is no evidence that alleles increasing type 2 diabetes susceptibility have been under positive selection in human populations. Which of the following is the best inference we can draw from these findings. Selected answer will be automatically saved. For keyboard navigation, press up/down arrow keys to select an answer. b C d Past selection for alleles increasing fat storage probably does not explain differences in type 2 diabetes prevalence in modern populations. Storage of excess carbohydrates probably does not contribute to type 2 diabetes. There is no genetic basis for differences between populations in type 2 diabetes. Fat storage has always been a deleterious trait for humans.arrow_forwardTwin studies are often used in the research of human behavioral traits. Although helpful, there are limitations to these studies. All of the following are limitations to twin studies EXCEPT: Traits are assumed to be simple Mendelian inheritance, discounting additive alleles and epistasis Dizygotic twins will often share more than 50% of their genes Monozygotic twins are often treated more similarity than dizygotic twins O Twins studies are a mechanism to understand the genetic and environmental components of a trait Twins reared apart are often adopted out to families of similar income, ethnicity, and religionarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSON
Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax
Anatomy & 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 & Company
Laboratory 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
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:PEARSON
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Anatomy & Physiology
Biology
ISBN:9781259398629
Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:9780815344322
Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:9781260159363
Author:Martin, Terry R., Prentice-craver, Cynthia
Publisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Biology
ISBN:9781260231700
Author:Sylvia S. Mader, Michael Windelspecht
Publisher:McGraw Hill Education