RC3: 7.A Quiz 3

The diagram represents possible genetic relationships between groups of organisms. Which statement is a valid conclusion that can be drawn from the diagram?

• Insects are more complex than mammals. 
• Sponges were the last new species to appear on Earth. 
• Earthworms and sea stars have a common ancestor. 
• Snails appeated on Earth before corals. 

While on an excavation, an archaeologist uncovers some bones. He suspects that they belonged to an early ancestor of today's modern horse. What is the best method to use to test this belief?

• Perform a cytochrome C of the two subjects. 
• Create a model showing the two organisms side by side.
• Perform a DNA comparison of the two subjects. 
• Create a linkage of bones from similar burial sites. 

Scientific illustrations of two skeletons are shown. The skeletons ont he left belong to a human and the skeleton on the right belongs to a gorilla. What evidence suggests that these species share a common ancestor?

• both species have large lower jaws
• both species have very small feet
• both species have eyes that face forward
• both species have extremely long necks

Lake Victoria, located in East Africa, holds over 200 species of cichlids. Cichlids are a type of fish with a unique "second" jaw in their throat. Wildlife biologists believe that Lake Victoria was initially colonized by one species of cichlids. These facts reveal that the other species of cichlids likely developed because different groups of the one species of cichlids-

• merged into one "super-group".
• ate all the available prey in Lake Victoria. 
• adapted until all of the groups developed small legs. 
• separated within the lake.

In 2009, Australian evolutionary biologist analyzed the DNA of two egg-laying mammals, the platypus and the echidna. They paired their findings with a paper on two fossils of similar life-forms from the early Cretaceous Period. The fossils from the early Cretaceous Period have DNA that is more similar to the modern platypus. By evaluating the scientific explanation offered by the researchers, a student could determine that genetic material-

• can be used to differentiate ancient and modern life-forms. 
• cannot be used to link ancient and modern life-forms.
• cannot be used to reveal information about ancient and modern life-forms. 
• can be used to show that ancient and modern life-forms are exactly the same.