Evolution Writing Prompts
1- Natural selection is a major mechanism through which populations
evolve. Describe three other mechanisms that can lead to evolution. In
a well- developed response address the following:
- define these 3 mechanisms that can lead to evolution (other than natural
selection).
- explain how these mechanisms are likely to lead to evolution in
populations
- give an example of how a population in which the three mechanisms are
operating will be affected.
2- Charles Darwin proposed that evolution by natural selection was the
basis for the differences that he saw in similar organisms as he traveled
and collected specimens in South America and on the Galapagos Islands.
Darwin’s Theory of Natural Selection States the Following:
 Organisms produce more offspring than can survive
 Variation (differences) exist in all populations
 Organisms best suited to environments will have more
offspring
 Over time organisms with certain advantageous variations
make up most of the population
In a well-developed response address the following:
(a) Explain the theory of evolution by natural selection as presented by
Darwin.
(b) Each of the following relates to an aspect of evolution by natural
selection. Using the explanation, explain the following (be sure to
give clear examples):
a. Natural selection and the formation of insecticide-resistant
insects or antibiotic-resistant bacteria
3- You are a scientist working in a remote area of the world. Recently, you
discovered a population of organisms that you think represents a new
species. To report this discovery to the rest of the scientific community,
you write an article to be published in a scientific journal that describes
these organisms and presents your reasons for proposing that this
population represents a new species.
Write an article in which you:
1. Describe the organisms in the newly discovered population.
2. Compare the discovered organisms to an existing population that you
report as the “original” population.
3. Explain the adaptation(s) that the discovered population exhibit(s)
that led to the process of natural selection, resulting in the “new”
population.
4. Explain the criteria that the discovered population exhibits that would
constitute a valid argument for it being considered a new species.
ANS:
Allow a maximum of 3 credits:
- 1 credit for defining three of the following four factors: gene flow as the movement of alleles from one
population to another, genetic drift as the changes in allele frequencies in a population due to chance,
sexual selection as occurring when certain traits increase mating success, and mutation as the formation of
new alleles.
- 1 credit for explaining that gene flow increases genetic variation; genetic drift reduces genetic variation;
sexual selection favors traits that increase mating success; mating introduces new alleles to the gene pool
- 1 credit for examples for three of the following four factors: gene flow, genetic drift, sexual selection,
and mutation. Sample answers: gene flow among two populations of ground squirrels when a few
individuals move from one population to the other; genetic drift (bottleneck effect) caused by a disease
that kills 90 percent of a population of tigers; male bighorn sheep butting heads to compete for females; a
mutation that results in an allele associated with a new fur color in foxes.