Part One: Video Lesson
Part Two: Practice Questions
1. Darwin found that on the mainland of South America, iguanas had small claws. This allowed them to climb trees in order to eat leaves. However, iguanas on the islands had large claws which allowed them to grip wet rocks in order to eat seaweed.
Which of the following statements below best describes the occurrence described above?
A. physical changes of the iguanas occurred over the course of generations to help them survive their environments, called adaptations.
B. The species on the islands must not have produced enough offspring because they could not climb trees.
C. Darwin’s conclusions were inconclusive because there was not enough variation to study.
Answer:A. physical changes of the iguanas occurred over the course of generations to help them survive their environments, called adaptations.
2. Read the following passage and then answer the question that follows:
Squirrels are a breed of animal seen all over the world. However, they possess many variations depending on where they live. For example, the Fox and Gray squirrel, while both squirrels, have many varying physical traits. The Fox squirrel have a rust colored belly and a black outline up their tail. Gray squirrels, on the other hand, are mostly gray, with a white tail. Fox and gray squirrels typically live in different areas. Their colors are a defense mechanism that allow them to easily blend into the forests in which they live.
Which of the terms and explanations below best describes the color difference found in the species of squirrels?
A. Variation explains why the squirrel species has varying traits like the coloring of their tails.
B. Natural Selection can explain why competition created scarcity and scarcity would explain their physical change.
C. Adaptation explains why both the Fox and the Grey squirrel have red tails.
Answer: A. Variation explains why the squirrel species has varying traits like the coloring of their tails.
3. Because a species can produce more offspring than can survive, which of the following results:
A. resources increase
B. resources decrease
C. resources remain the same.
Answer: b. resources decrease