AP BIOLOGY

Detailed explanation-1: -A vestigial structure in one organism can be defined as a reduced form of a functional structure in another organism. Natural selection is based on the concepts of excess reproduction, variation, inheritance, and the advantages of certain traits.

Detailed explanation-2: -Structures that have no apparent function and appear to be residual parts from a past ancestor are called vestigial structures. Examples of vestigial structures include the human appendix, the pelvic bone of a snake, and the wings of flightless birds.

Detailed explanation-3: -Vestigial structures are homologous to fully functioning structures inherited by related lineages. Thus, they provide strong evidence of common ancestry and can help us trace the evolutionary origin of the species with the vestigial structures.

Detailed explanation-4: -Homologous structure. Structure that are similar in different species due to common ancestry. Vestigial structure. Structure that is non-functional, or reduced in function. Analogous structure.

Detailed explanation-5: -A vestigial structure is a biological structure that has lost a major ancestral function and is usually drastically reduced in size. Well-known examples include the eyes of blind cave fishes and blind cave salamanders, and the diminutive wings of kiwis and emus.