BIO 311D

• You find a section of sedimentary rock in which the strata and some fossils have been exposed. You notice that a clam fossil is in deeper strata than a fish fossil. Using relative dating, which fossil is most likely older?

  clam
• Imagine two species that are thought to have a recent common ancestor. If this idea is correct, these two species most likely have ________.

  several homologous structures
• Darwin recognized that fitness is a function of the organism’s interaction with its environment. Which would not be an aspect of an organism’s environment that could affect its fitness?

  its birth weight
• MRSA infections are occurring at alarming rates. One reason for this could be that people do not finish their antibiotics. Which of the following is the most likely reason that this could lead to something like MRSA?

  The first few days of antibiotics kill off the most susceptible bacteria, making people feel better. Then, when people stop taking the antibiotics, the less susceptible bacteria that survived have been selected and reproduce to create a more resistant population.
• Imagine a species of bird in which females prefer to mate with brightly colored males. However, males with bright backs are more often preyed upon by hawks. Assuming that a wide variety of genetic variation exists in the species, which do you think is the most likely evolutionary outcome?

  Males will be selected to have bright chests and dull backs.
• Darwin was greatly influenced by contemporary geologists such as Hutton and Lyell. Which of their ideas was the main influence on Darwin’s thinking?

  Large-scale geologic change is the result of gradual accumulation of slow, continual processes.