Unit Test — Unit test Answers

Henry was studying two populations of the same species of lizards. One population lived on an island and the other lived on the mainland. Both populations were affected by a hurricane that hit the island and the mainland with equal force. A year later, Henry was testing the gene frequency and saw a decrease in genetic variation in the island species, but not in the mainland species. Which best describes a conclusion he might have reached?

Horses and zebras can be bred to produce a zorse, which is infertile. Which is most likely the reason zebras and horses are considered separate species?

Charles Darwin hypothesized that some individuals would be better equipped for survival than others, and that those that were less equipped would not survive. Darwin formulated this hypothesis based on the work of which scholar?

A biology teacher asks students to give examples of genetic variations that support the idea that changes in a population’s environment affect genetic variation. Which is the least supportive example?

Mr. Morales is teaching a lesson on classification. He says that spiders are classified as a different group than insects because they have eight legs instead of six legs. He explains that spiders evolved first. Mr. Morales also says that having eight legs is the derived trait that separates the two groups. Antonio thinks Mr. Morales is wrong. Which piece of information is Antonio considering?

In a cladogram, when does a group of organisms branch off?

Which type of selection leads to increased phenotypic and genetic variation?

Which best illustrates a result of natural selection?

Why are the Miller-Urey experiments essential to the theory of evolution?

A student has written a paper about a deer population that was separated when a canyon developed between members of the group. In her paper, she showed that the two groups adapted differently and can no longer interbreed. What would be the best title for her paper?

Scientists notice structural similarities between fossils of a land animal and an aquatic organism. They know the similarities are not a result of the two organisms having to adapt to similar environments. What can they attribute the structural similarities to?

Which best describes biogeographic isolation?

Thylacosmilus is a marsupial, and Smilodon is a mammal. Thylacosmilus and Smilodon both have saber teeth, but they do not share an ancestor that had saber teeth. What are saber teeth for these organisms?

Which of the following is an example of reproductive isolation?

A male cardinal’s red color is an example of a trait affected by natural selection. The females of the species choose mates based on the vibrant colors of the males’ feathers. If females begin using different criteria than feather color when they choose mates, what would most likely happen to the color of the male cardinals over time?

Evolution is change in a population over time and includes the gene pools of that population. How does biogeographic isolation allow for the change of gene pools over time?

Consider the two male oryx that are shown below.Which of Charles Darwin’s main points is depicted in the image?

Which of the following best defines a gene pool?

Consider the generalized cladogram of fish.A fossilized fish is found that has jaws but no true bones. Where does this fossil belong on the cladogram?

A scientist is trying to determine the relationship between clams, snails, and squid. When she generates a molecular clock, she is surprised to see that clams and squid are more closely related than clams and snails. Which did the molecular clock data show?