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* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Division 2 MST Genetics 2011-2012 What is our impact on Biodiversity? Skill Addressed: Systems Thinking Content: Genetics Black-footed ferret Information About the Ferrets Black-footed ferrets are long, slender animals. The average size is 18 to 24 inches long including a 5 to 6 inch tail, and 1½ to 2½ pounds in weight. Males tend to be slightly larger than females. With the exception of breeding season and females caring for their kits, black-footed ferrets are solitary animals. They are nocturnal (most active at night) and fossorial (live mostly underground) predators. (http://blackfootedferret.org/animalprofile) The Problem Having survived years of predation by golden eagles, great horned owls, and coyotes, the black-footed ferret almost succumbed to the all-out war waged by humans on another species, the prairie dog. Ranchers and farmers spent decades destroying the prairie dog towns of the Great Plains. This impacted the ferrets because they eat little other than the prairie dogs and they obtain shelter by taking over the burrows created by the prairie dogs. It takes a lot of prairie dogs to sustain even a small population of ferrets. Black-footed ferret population numbers were frightfully reduced by the 1950s, and feared extinct in 1979! A small population was discovered in Wyoming in 1981, but that population was nearly wiped out by a plague, followed by an epidemic of canine distemper. The last 18 survivors of the population were taken into a captive breeding program to assist in the species’ recovery. In recent years, the ferrets have been re-introduced into the wild and their population has grown to over 400 individuals. (Text taken from The Company We Keep by Douglas H. Chadwick and Joel Sartore) The goal of this assessment is for you to show your understanding of how the chances of survival of a population and its offspring depend upon their gene pool. Division 2 MST Genetics 2011-2012 Your task In this assessment you will analyze how the gene pool of a small population of a species affects their chances of survival in their habitat. The small population in question is that of black-footed ferrets that survived after a catastrophic mid-summer fire in their prairie habitat that decimated the original colony by killing all but 10 survivors, 5 male and 5 female. For the assessment we will concentrate on 9 traits: Alleles in Population Trait* Letter Camouflage Dominant Recessive C 10 10 Precise vision P 12 8 Accurate sense of smell A 10 10 Strong claws and forearms S 14 6 Healthy jaw formation H 16 4 Agility G 8 12 Acute hearing E 10 10 Healthy rate of reproduction R 16 4 Immunity to canine distemper D 14 6 Step 1: Determine the gene pool of your population: 1. Choose 3 traits, which you deem to be most important for survival after reading the background information (you will need to justify your decision later so choose wisely!) 2. Write in the genotypes for the 10 ferrets in the chart below: Female Ferrets Ferret Trait 1: Trait 2: Trait 3: 1 2 3 4 Male Ferrets 5 6 7 8 9 10 Division 2 MST Genetics 2011-2012 Step 2: Analyze your population **** TYPE your answers to the following questions: **** 1. Based on the genotypes of your ferrets, which 3 ferrets are most likely to survive and produce offspring? Support your response with evidence from the background information. 2. Based on the gene pool of the population, explain whether or not your ferret population is genetically equipped to survive the environment in future generations. Give at least 3 different examples using monohybrid crosses to show probabilities of offspring. 3. Ferret parent 1 (P1) is immune to canine distemper. She is crossed with male ferret parent 2 (P2), and they produce a first generation of Ferret pups (F1) that are ALL immune to canine distemper. Because of the small ferret population, inbreeding occurs and the F1 mate (with each other) to produce the second generation (F2) of ferrets. A canine distemper outbreak occurs and some of the F2 offspring die. What are the possible genotypes of: F2, F1 and both parents (P1 and P2)? Make a diagram to show the relationships and genotypes. 4. In your own words, explain what is meant by genetic variation, and why it is important. 5. A) Explain why two ferrets have a low probability of producing two identical pups (non-twins). B) Given the 3 traits you chose, what is the probability that ferrets 5 and 6 will produce offspring that are non-twin identical for the 3 traits. 6. What are 2 ways that meiosis results in genetic variation? Include a description of the meiosis phases involved. Diagrams that you create may be helpful in explaining your answer. 7. Using the ferrets’ background information and what we’ve learned in class, discuss 2 factors that would cause a change in the allelic frequencies of the ferret population. 8. Given parents that have the genotypes CcEe and ccee, determine what percentage of offspring from the F1 generation would be in danger of an increase in the great horned owl population of this habitat. Be sure to show your work. Division 2 MST Genetics 2011-2012 Step 3: Conclusion Write a concluding statement that answers the question: how do the chances of survival of a population and its offspring depend upon their gene pool. (Be sure to use examples from this assessment and/or class activities to support your statements, and use the following concepts in your response: Allele frequency, Dominant, recessive, variation, survival fitness)