1) Many organisms have the ability to reproduce asexually as well as perform sexual reproduction. A Scientist, John Smith, was conducting research on aphids that can undergo both methods of reproduction. He determined the males in his population had fertilization rate of 1.8 and a relative fitness of outcrossed offspring was 1.1. a) What is the equilibrium frequency of males in this population? b) Is this population stable equilibrium and why?

The Forbes sea star and common sea star are broadcast spawners that are known to hybridize, yet they exist as separate, genetically distinct species (unique branches on the tree of life). One mechanism that may contribute to their uniqueness is prezygotic reproductive isolation, which is the incompatibility of gametes (sperm and eggs) from separate species. We know they hybridize, so the eggs and sperm are compatible, but could gametes from the different species be less compatible than the gametes from each individual species? Harper & Hart (2005) addressed this question in a series of cross-fertilization experiments. Did they find evidence that gametes ‘preferred’ to cross with gametes of the same species? Explain your answer.

If 9% of an African population is born with a severe form of sickle-cell anemia (ss), what percentage of the population will be more resistant to malaria because they are heterozygous (Ss) for the sickle-cell gene? Assume Hardy-Weinberg conditions. Submit your answer as it is. a) homozygous recessive individuals (q²) b) the recessive allele (q) c) the dominant allele (p) d) homozygous dominant individuals (p²) e) heterozygous individuals (2pq)

You are performing a series of experiments on fruit flies.  You have a true breeding population of flies with red eyes, and a true breeding population of white eyes.  You breed the population of flies to each other to get an F1 generation.  In this F1 generation, 75% of the flies have Red eyes, 25% of the flies have white eyes.   All the female flies have red eyes, half of the male flies have white eyes and the other half have red eyes. A statistically significant number of baby flies were produced in this cross. 1) What is that number? 2) What is the genotype ratio of the F1 generation?  Give the genotypes.

____ refers to the collection of all alleles across all gene loci in a population. a) Genetic drift b) Genotype c) Gene pool d) Gene flow

The following table provides phenotypic data for a population of mammoths living in cold environments based on fossil and DNA evidence. Based on this data and your knowledge of natural selection, which explanation best explains the trends seen in the data? Individuals with thicker fur had a survival advantage in the cold environment, allowing these individuals to reproduce more often and create more offspring.   Individuals within this population of mammoths tend to only mate with individuals that have thick fur.   This population of mammoths appear to be in Hardy-Weinberg equilibrium since no allele frequencies are changing over time.   Individuals with thick fur migrated into the population of mammoths, increasing the proportion of these individuals.

Could a set of invading genotypes with the “parachute” strategy take over a population that originally consists of only “jumpers without parachutes”? Or can populations of 100% individuals that sacrifice their fitness to benefit non-relatives outcompete a population of individuals who only sacrifice fitness to benefit their kin?  Give a reason for your answer.

2) An investigation of yellow croaker tail fin length showed that the length of fins varied from 36mm to 81mm. In one generation recorded out of a population of 3,980 fish only three had fins as long as 81mm. i) How many genes and ii) how many alleles are likely to be involved in the determination of this quantitative trait? and iii) what is the contribution of each dominant allele to the fin length? a) In one cross between fish both with 59 mm fins it was found that the offspring all b) had fins between 58 and 60 mm long. However, when the cross was repeated with another pair of 59mm fish\, this time the offspring tails varied between 36 and 81 mm long. Specify possible parental genotypes for the fish used in; i) the first cross and, ii) the second cross. In another cross a new true-breeding fish variety was used which gave a range of c) F, tail fin lengths that had a variance of 0.431. In the crosses using the original variety there was an even greater range of fin lengths and a…

Gene flow can have one effect in the context of a single population, and a different effect in the context of two populations that were recently isolated from one another. Describe with specificity the effect that gene flow has a) on a single population, as well as b) on two populations that were recently isolated from one another.

Which of the following mechanism(s) will lead to a decrease in heterozygosity? Select all that apply. Multiple correct  - genetic drift - migration - positive assortative mating - mutation - negative assortative mating   I tried genetic drift, negative assortative mating and mutation - that was incorrect I also tried genetic drift and negative assortative mating - that was also incorrect Lastly, I tried positive assotative mating, genetic drift and migration - that was also incorrect