1. Which of these best illustrates natural selection?

2. Which statement best describes natural selection?

3. Over time, new species have evolved while others have become extinct. Which of the following most likely supports how giraffes evolved long necks?

4. How is natural selection in the evolution of long necks in giraffes best explained?

5. Rainfall in a tropical region is below average for 10 consecutive years. Insect species adapted for dry conditions are much more plentiful at the end of the 10 years. Which of the following statements best explains the increase in the population of these insects?

6. A species of finch has been studied on one of the geographically isolated Galapagos Islands for many years. Since the island is small, the lineage of every bird for several generations is known. This allows a family tree of each bird to be developed. Some family groups have survived and others have died out. The groups that survive probably have

7. A population of termites initially consists of darkly colored and brightly colored members. After several generations, the termite population consists almost entirely of darkly colored members because the brightly colored termites are easier for a predatory species of insectivores to locate. This situation is an example of

8. The arctic fox and gray wolf are two examples of animals that change the color of their fur with the seasons. IN the summer, the animals are a brownish color, and in the winter, they turn white. The change of color helps the animals to survive. Which of the following provides the best explanation for this change?

9. The Venus flytrap plant lives in soil with a few nutrients. The plant absorbs nutrients by trapping insects inside its leaves. The ability of the Venus flytrap to trap insects is an example of which of the following?

10. C. reinhardtii is a species of unicellular green algae that primarily produces energy for growth through photosynthesis. However, when necessary, they can also produce energy from a carbon source, which allows them to grow in total darkness. A scientist grows a population of this algae in the dark and finds that after 600 generations, the algae population now grows better in the dark than in the light. Which statement best explains what has happened to the cells in the algae population?

12. A lizard species mostly eats fruit from one particular type of tree. If a virus kills most of these trees, which individual lizards will most likely survive?

13. Which adaptation prevents armadillos from being eaten by predators?

21. Two rabbits live in the same forest. One rabbit has a thin fur coat in the summer and grows a thicker fur coat during the winter. The other rabbit has a thin fur coat year-round. Which best describes what could happen during a cold winter?

24. Some students are observing the behavior of a male bird in the schoolyard. Which of the following observed behaviors might increase the probability of reproductive success?

25. The Articum lappa plant produces prickly burrs that grow on the ends of the stems. These burrs can easily catch on the fur of animals. This plant structure most likely benefits the plant in which of the following ways?

26. Students visiting the zoo observe a male peacock spreading his feathers in the presence of a female peahen. This behavior most likely helps the peacock–

27. Male widow birds (Euplectus progne) have very long tail feathers. What evidence would support the claim that these tails are used by the birds to attract mates and lead to reproductive success?

28. Which of the following plant adaptations allows plants to use animals to transport their seeds to new locations?

29. Which of the following would provide the best evidence that genetic factors influence the growth of plants?

31. Students treated a population of bean plants with fertilizer. They observed that these plants, on average, were taller than another population of the same kind of bean plants that were not treated with fertilizer. These observations lend support to which of the following conclusions?

32. Students planted several radish plants (Raphanus sativus) in their school garden. Students were allowed to take some of the plants home. One student observed that the plants grown at home were taller and had more leaves. She proposed the idea that genetic differences were responsible for the differences between the plants grown at school and the plants grown at home. Which of the following is the best argument against this idea?

33. Which of the following procedures would provide the best data to test the effect of daylight hours on the number of blooms on rose bushes?

34. In a given population of plants there is variation in the time of day when flowers open. Those individual plants with flowers that open at night would be more likely to pass on this trait in an environment dominated by what?

35. Scientists have concluded that snakes evolved from an ancestor with legs. Which of the following statements provides the best evidence for this conclusion?

36. Which statement describes the best evidence that two species share a recent common ancestor?

37. More than 1.5 million species of animals have been described, yet all of them have DNA that is made of the same building blocks. This is evidence that all animals have

38. Skeletal structures are common between two animals of different species. These structures probably exist because both species

49. Comparing the embryos of different animals can show relationships that can’t be seen when comparing the fully formed animals. Why is this the case?

50. The embryos of two different organisms are observed to have similar features. What is the most reasonable conclusion that can be drawn from this observation?