EH Chapter 2 Practice Quiz

This fossil bird and this living salamander both have tails. However, they have different tail structures. The bird has a very short tail made of just one bone that helps it have a light skeleton for flying. The salamander has a long tail with many bones that helps it balance while it runs. What most likely explains why both the bird and salamander have tails and why the tails are different?

• The salamander and bird both inherited tails from a shared ancestor population, but this population separated into different environments. In each environment, different types of tails evolved, which helped the populations survive.
• It is impossible to explain the body structures of different species. The way that structures change over time is very complex, and no one has ever observed these changes occurring.
• The bird and salamander are different species, so they do not share an ancestor population. These species had separate ancestor populations, and each evolved a tail that helps it survive in its environment.
• All species have their own specific body structures, so it is a coincidence that the bird and salamander happen to have different types of tails.

This sea anemone and this ctenophore both have tentacles, which are body structures that help them catch food. However, sea anemone tentacles are short and can sting, while ctenophore tentacles are long for grabbing and cannot sting. What most likely explains why both species have tentacles and why the tentacles are different?

• Sea anemone and ctenophore both inherited tentacles from a shared ancestor population, but this population separated into different environments. In each environment, different types of tentacles evolved, which helped the populations survive.
• It is impossible to explain the structures of different species. The way structures change over time is very complex, and no one has ever observed these changes occurring.
• This sea anemone and ctenophore are different species, so they do not share an ancestor population. These species had separate ancestor populations, and each evolved tentacles that help it survive in its environment.
• All species have their own specific body structures, so it is a coincidence that the sea anemone and ctenophore happen to have different types of tentacles.

The body structures for a population of green herons (a species of bird that lives near water) were stable for a long time. Then, their body structures changed to make the green herons taller. Why did this happen?

• It is impossible to say without more information.
• The green heron population wanted to be taller.
• Their environment must have changed.
• Organisms naturally become taller over time.

This octopus and this surf clam both have a body structure called a mantle, which covers their soft bodies. However, the mantle is shaped differently in the two species. The octopus’s mantle has muscles that help the octopus swim. The surf clam’s mantle helps the clam build its shell. What most likely explains why both the octopus and surf clam have mantles and why the mantles are different?

• All species have their own specific body structures, so it is a coincidence that the octopus and surf clam each happen to have mantle structures that are different.
• The octopus and surf clam are different species, so they do not share an ancestor population. These species had separate ancestor populations, and each evolved a mantle that helps it survive in its environment.
• It is impossible to explain the body structures of different species. The way that structures change over time is very complex, and no one has ever observed these changes occurring.
• The octopus and surf clam both inherited the mantle structure from a shared ancestor population, but this population separated into different environments. In each environment, different types of mantle evolved, which helped the populations survive.

This tortoise and this moray eel both have jaws that help them grab food. However, they have different structures in their jaws for eating. The tortoise has a bony beak that helps it bite plants. The moray eel has sharp teeth that help it eat fish. What most likely explains why both have jaws and why the jaws are different?

• All species have their own specific body structures, so it is a coincidence that this tortoise and moray eel each happen to have jaws that are different.
• Tortoises and moray eels are different species, so they do not share an ancestor population. These species had separate ancestor populations, and each evolved jaws that help it survive in its environment.
• It is impossible to explain the structures of different species. The way structures change over time is very complex, and no one has ever observed these changes occurring.
• Tortoises and moray eels both inherited jaws from a shared ancestor population, but this population separated into different environments. In each environment, different types of jaws evolved that help the populations survive.

The body structures for a population of chimpanzees were stable for a long time. Then, their body structures changed, making the chimpanzees stronger. Why did this happen?

• Organisms naturally become stronger over time.
• It is impossible to say without more information.
• The chimpanzee population wanted to be stronger.
• Their environment must have changed.

What is a part of an organism (for example, one or more bones) called

• ancestor
• body structure
• fossil
• trait

What is a common ancestor population?

• a more recent species that evolved from an ancestor population
• an older population from which two or more newer species descended
• a part of an organism (for example, one or more bones)
• the process by which species adapt to environmental changes over a very long time

What is the process by which species adapt to environmental changes over a very long time?

• descendent species
• generation
• evolution
• mutation

What is a scientist who studies fossils in order to understand the ancient history of life on Earth called?

• Botanist
• Chemist
• Historian
• Paleontologist