Question

Evolution is an accepted biological process that remains poorly understood by the wider public. A source of this confusion is a misunderstanding of the very mechanism that drives evolution of populations over time.

a. What is the basic mechanism of evolution and how does it occur?

b. Why would you expect to see a greater resilience and also potential change in sexually reproducing organisms compared to asexually producing ones?

c. What are two selection patterns? Give scenarios to explain each?

d. What are the two types of evolution and how could we measure each?

e. What are four factors that can lead to speciation?

Answer 1

a) Natural selection, mutation and genetic drift are some of the basic mechanism of evolution. Natural selection helps the organisms to cope up in harsh condition and to adopt accordingly with the changing environment which causes evolution. Mutation helps in formations of new alleles which either leads to death of individuals or make them more fit to the environment. Due to sampling error the allelic frequencies change in a population from one generation to next which leads to evolution.

b) Sexual reproduction involves combination of gametes from two parents which leads to variation in every generation, creates genetic diversity and make the offspring more fit to the environment.

d) Micro-evolution and Macro-evolution are the two types of evolution. Micro-evolution do not form new genes while Macro-evolution are the results of formation of new genes. Micro-evolution can be measured by calculating change in gene frequencies. Macro-evolution can be measured by geologic time scale.

e) Factors that can lead to speciation involves: Geographical isolation,Gene flow, Hybridization, Genetic drift, Natural selection, Reproductive isolation.