Question

1. when you culled the white individuals in the simulation, this was an example of ___.

a) stabilizing selection
b) directional selection
c) disruptive selection
d) sexual selection

1. in a very small population the allele frequencies can change simply due to chance events. this is called ___.

a) natural selection
b) artificial selection
c) founder effect
d) genetic drift
e) gene flow
f) unusual

1. which of the following are non - adaptive mechanisms of evolution

a) mutation
b) genetic drift
c) genetic bottlenecking
d) immigration
e) all of these

1. which of the following is an example of a population undergoing natural evolution today?

a) super strains of bacteria like mrsa that are resistant to antibiotics
b) stronger and more pest - resistant corn crops engineered in labs
c) human population is better able to see with technologies like lasik and cataract surgeries
d) fewer babies are born with appendices (the appendix) these days because we are better able to remove them from adult patients

Explanation:

• Question 7: Directional selection favors one extreme phenotype. Culling white individuals (assuming a color - related trait) is an example of favoring non - white individuals (one extreme), so it is directional selection.
• Question 8: Genetic drift is the change in allele frequencies in a small population due to chance events.
• Question 9: Mutation (random genetic changes), genetic drift (chance - based allele frequency changes in small populations), genetic bottlenecking (a severe reduction in population size leading to random allele frequency changes), and immigration (random movement of genes into a population) are all non - adaptive mechanisms of evolution.
• Question 10: Super strains of bacteria like MRSA that are resistant to antibiotics are evolving naturally as bacteria with antibiotic - resistant genes survive and reproduce more in the presence of antibiotics. Engineered corn (B) is artificial selection, LASIK and cataract surgeries (C) are technological interventions, and appendix removal (D) is a medical procedure, not natural evolution.

Answer:

1. B. directional selection
2. D. genetic drift
3. E. all of these
4. A. Super strains of bacteria like MRSA that are resistant to antibiotics