Biological Evolution

This fossil turtle and this living hawk both have a structure in their neck called the atlas bone. What best explains why both species have an atlas bone?

• The turtle and hawk are different species, so they must not share an ancestor population. They inherited their atlas bone structure from separate ancestor populations.
• The turtle and hawk both share the same ancestor population that had an atlas bone. They inherited this structure from the ancestor population.
• It is impossible to say. Fossils are very old; therefore, we cannot make observations of the turtle’s ancestors, and we cannot explain its body structures.
• All species have their own specific body structures, so it is a coincidence that this turtle and hawk each happen to have the atlas bone structure.

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

This fossil pterodactyl and this living elephant both have a bone in their hip called the ilium. What best explains why both species have an ilium?

• The pterodactyl and elephant both share the same ancestor population that had an ilium bone. They inherited this structure from the ancestor population.
• All species have their own specific body structures, so it is a coincidence that the pterodactyl and elephant each happen to have the ilium bone structure.
• It is impossible to say. Fossils are very old; therefore, we cannot make observations of the pterodactyl’s ancestors, and we cannot explain its body structure.
• The pterodactyl and elephant are different species, so they must not share an ancestor population. They inherited their ilium bone structures from separate ancestor populations.

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

What is a homologous structure?

• having a body part that has no known function
• similar structures in more than one organism because they evolved from a common ancestor
• similar structures that evolved independently in two living organisms to serve the same purpose
• a structure that evolved to help an organism survive in their environment

Tags

NGSS.MS-LS4-2

European moles and Sumatran tigers both have eyes. However, European moles live completely in the dark and have very small eyes, while Sumatran tigers have large eyes that can see prey from far away. What most likely explains why both European moles and Sumatran tigers have eyes and why their eyes are different?

• The European mole and Sumatran tiger both inherited eyes from a shared ancestor population, but this population separated into different environments. In each environment, different eye types evolved, which helped the populations survive.
• All species have their own specific body structures, so it is a coincidence that the European mole and Sumatran tiger each happen to have different types of eyes.
• The European mole and Sumatran tiger are different species, so they do not share an ancestor population. These species had separate ancestor populations, and each evolved the type of eyes that help 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.

Tags

NGSS.MS-LS4-2

NGSS.MS-LS4-4

Whales live in the ocean. They do not have legs, but they do have a pelvis with small leg bones attached to it. This is evidence that:

• Whales are not well adapted to ocean life.
• Whales do not have homologous structures
• Whales evolved from animals that once lived on land
• Whales evolved from some type of fish

Tags

NGSS.MS-LS4-2

What is speciation?

• the ending or extinction of a single species
• the process of a single species changing gradually over time
• a single species has homologous structures with another species
• a process of some members of the species evolving into a separate species

Tags

NGSS.MS-LS4-2

NGSS.MS-LS4-4

This fossil trilobite and this living blue crab both have a limb structure called a biramous limb. What best explains why both species have biramous limbs?

• It is impossible to say. Fossils are very old, so we cannot make observations of the trilobite’s ancestors, and we cannot explain its body structures.
• The trilobite and blue crab both share the same ancestor population that had a biramous limb. They inherited this structure from the ancestor population.
• All species have their own specific body structures, so it is a coincidence that this trilobite and blue crab each happen to have the biramous limb structure.
• The trilobite and blue crab are different species, so they must not share an ancestor population. They inherited their biramous limb structure from separate ancestor populations.

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

Which of the following is a vestigial structure?

• stomach
• heart
• wisdom teeth
• brain

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

Which of the following is NOT a vestigial structure?

• appendix
• lungs
• coccyx
• ear muscle

Tags

NGSS.MS-LS4-2

Which one of these is an example of a vestigial organ?

• human coccyx
• human stomach
• human brain
• human liver