Reference no: EM133392514
Questions
1. If you are working as a evolutionary biologist and decide to study a charismatic plant species that grows in Piedmont Prairies, purple coneflower, Echinacea angustifolia. It is well documented that the establishment and expansion of agriculture over the past two centuries has dramatically reduced abundance of this and other species native to the once vast Minnesota prairies. In your study area, you find 15 widely separated sites (up to a km apart) that had never been plowed. Each of the sites harbors 10-20 Echinacea individuals. Searching with a team of dedicated graduate students, you also find one relatively large area with many long-lived species characteristic of undisturbed prairie, including a population of several hundred Echinacea individuals at considerable distance (3 km) from all of the 15 smaller population remnants.
2. What evolutionary process(es) do you think, based on your understanding of evolutionary principles, is/are likely to be having more substantial effect on change in the genetic composition of the small populations compared to the larger population?
3. Considering allele frequencies for the small populations (at each of the individual loci you assayed), what general characteristic do you expect to find? And how might the allele frequencies for the set of small populations compare to the allele frequency at each locus of the large population? Explain your reasoning.
4. What differences do you expect to find when you compare the genotypic composition of the small populations with that of the large population? Explain your reasoning.
5. Natural selection (i.e. differential survival and reproduction in relation to heritable traits) is a key evolutionary process and the sole basis for adaptive evolution of populations. Darwin viewed adaptation by natural selection as a very slow process, but there is increasing recognition that it may proceed rapidly under conditions that promote it (as you laid out in the previous problem set). Evolutionary change via artificial selection (by humans), as in this question, can also proceed rapidly and has illuminating similarities to natural selection.