I’m Looking Over a White-Striped Clover by Evarts, Krufka, and Wilson

Part IV—What Did You Learn?

You have already thought about and used several concepts from evolutionary biology that aid in our understanding of how organisms adapt to their habitats. Now let’s formally define them.

Variation
Differences among individuals of a species; different forms of the same trait.
Natural Selection
Differential survival and reproduction of individuals bearing different forms of the same trait.
Evolution
Genetic change in a population over time.
Adaptation
The evolution of a trait that increases the likelihood of survival and reproduction of an organism in a particular environment.

Exercise 8

  1. What are examples of variation in the clover?
  2. Refer back to Figure 1 showing the relative frequency of plain and striped clover in Minnesota and North Carolina. Explain why there is variation in the frequency of each type of white clover between each of these areas.
  3. Adaptation in the white clover means that over time there is an increase in the frequency of particular traits that would help individuals in that population of white clover survive and reproduce in that particular habitat. What are examples of possible adaptations in the clover? Remember, adaptations are specific to a particular habitat.
  4. Comparing the white clover populations in Minnesota and North Carolina, what would you need as evidence that evolution has occurred?
  5. Several factors may exert selection pressure on different traits in white clover in each habitat. What factor would you propose is exerting the strongest selection pressure on the production or nonproduction of CN in white clover in Minnesota? In North Carolina?

Go to Part V—“Checking Your Understanding”

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