ANS3701 Assignment 6 Semester 2 Due 30 September 2024

Question 1 In conservation genetics, heterozygosity is a fundamental measure of genetic diversity within a population. For example, if a population of leopards has an observed heterozygosity (Ho) of 0.35, this means 35% of individuals possess different alleles at a given genetic locus. In comparison, expected heterozygosity (He) represents the level of genetic variation expected under random mating, and a much higher He value of, for example, 0.52 would indicate potential inbreeding or genetic drift, thus reducing diversity in this population. The inbreeding coefficient (Fis) quantifies the extent of inbreeding, with values closer to 1 suggesting higher levels of inbreeding. If a population of leopards shows a Fis of 0.33, it points to a significant reduction in genetic diversity compared to a connected population with a lower Fis of, for example, 0.05. When populations experience events like genetic bottlenecks, where population numbers decrease drastically, allele frequencies become skewed, resulting in reduced allelic richness (i.e. the number of alleles per locus). This can be detected through genetic tests like the M-ratio, where a low value may signal the effects of a bottleneck. 2 Effective population size (Ne) refers to the number of individuals contributing to the next generation's gene pool (i.e., the number of reproductive individuals in a population) and is often lower than the censused population size due to factors like unequal sex ratios or varying reproductive success. For example, if a population census size is 120 but the Ne is only 40, this would indicate genetic vulnerability even though the actual population size is quite large. Consider the following scenario and answer the questions that follow. You are part of a team of conservation biologists working to conserve an isolated population of leopards in a remote region. Due to habitat fragmentation, the population has been separated from neighboring populations for several decades. Preliminary studies have indicated a decline in genetic diversity, raising concerns about the longterm viability of this specific leopard population. Your task is to assess the genetic health of this population and recommend strategies for its conservation. You collected tissue samples from 30 individuals in the isolated population to assess the population’s genetic diversity. After extracting DNA from the tissue samples and using microsatellite markers, you determine the following genetic diversity indicators: Observed heterozygosity (Ho): 0.20 Expected heterozygosity (He): 0.52 Number of alleles per locus (A): 4 1.1 Explain in your own words how the observed heterozygosityboat compares to the expected heterozygosity and what this suggests about the population. (2) 1.2 Using the data collected, you calculate the inbreeding coefficient to be Fis = 0.65. However, results from another population which is not isolated from other populations had a Fis value of 0.09. 1.2.1 What does the higher Fis value suggest about the isolated population? (2) 1.2.2 What are the possible consequences of inbreeding in this population? (2) 1.3 Using a diagram, explain what a genetic bottleneck is. (2) 1.4 How does a genetic bottleneck affect allele frequencies and genetic variation in a population? (2) 1.5 What management strategies would you propose to mitigate the effects of a past bottleneck? (3) 3 1.6 You estimate the effective population size of the isolated population to be around 40, would you expect the effective population size to be smaller or larger than the actual population size? Explain your answer. (3) 1.7 Why is maintaining a larger Ne important for long-term population viability? (1) 1.8 Which options could you consider when proposing a genetic rescue plan for the population? (3) Question 2 (10