Practise AP Biology 7.1 questions by connecting heritable variation and environmental pressure with fitness, reproductive success and population change.
Many species of corals are threatened by the increasing temperatures and decreasing pH of ocean waters. One species, Stylophora pistillata, has been found to thrive in water that is warmer and has a lower pH than the water that corals typically thrive in. Additionally, researchers have found that the tolerance for the new water conditions is heritable.
Which of the following statements best explains the changes seen in S. pistillata in response to the changing water conditions?
The corals' adaptation is an example of natural selection because the tolerance is in response to a changing environment and has a genetic basis.
The corals' adaptation is an example of the founder effect because the majority of corals do not have a tolerance for warmer water.
The corals' adaptation is an example of genetic drift because the change was a chance event and not the result of selection in response to environmental change.
A
Existing isolated brook trout populations in Newfoundland, Canada, were once part of a larger population that was fragmented at the end of the most recent glaciation period about 10,000 to 12,000 years ago. Researchers investigated 14 naturally separated stream populations of brook trout. They found that the populations are all genetically distinct and show differences in morphology.
Brook trout with longer fins are able to swim faster than brook trout with shorter fins. In one of the Newfoundland streams, the main prey of the brook trout evolved to move faster. For brook trout living in this stream, explain the difference in fitness between longer-finned individuals and shorter-finned individuals.
- Individuals with longer fins are more likely to capture prey and reproduce.
1 point