16.4 Evidence for Evolution

Structures with the same parts have different functions; suggests that organisms share a common ancestry

• vestigial structures
• homologous structures
• adaptive radiation
• fossil

If an organism has a vestigial structure, that structure likely once had a function in a(n)

• close relative
• early ancestor
• unrelated organism
• embryological stage

Whales are aquatic mammals that contain a pelvis bone.  Even though it does not aid in its movement, the function must have been used by a common ancestor of the whale.  Thus, the pelvis is referred to as a(n)

• vestigial structure
• analogous structure
• homologous structure

A category of body structures that are formed in similar ways during embryonic development and share similar patterns of bone structure.

• Homologous structures

• Analogous structures

• Vestigial structures

• Bone structures

What type of structure does this image illustrate?

• Analogous structures

• Homologous structures

• Vestigial structures

Select the two most important characteristics that distinguish homologous structures.

• Similar bone structures

• Similar function

• Similar embryonic development

• Similar species

What type of structure does this image illustrate?

• Homologous structures

• Analogous structures

• Vestigial structures

What are the most important characteristics of analogous structures?

• Structures that perform the same function

• Structurally different

• Structurally the same

• Structures that perform different functions

Does the presence of homologous structures in genetically different animals suggest common ancestry?

• Yes

• No

Which of the following is NOT considered a vestigial structure in humans?

• Eye lashes

• Appendix

• Wisdom teeth

• Tail bone