Assignment #6 Anatomical Similarities And Differences Mrs. McCarthy Biology Tuesday, September 18, 2018

Comparative Anatomy- the study of similarities and differences in the anatomy of organisms A. This demonstrates similar evolution and common ancestors among different species

B. Homologous Structures- structural features with a common evolutionary origin that may or may not be similar in function and appearance 1. Examples: Bones in the appendages of these animals a. Bat b. Whale c. Cat d. Pig e. Crocodile f. Human

Homologous Structures

C. Analogous Structures- Body parts of organisms that do not have a common ancestor but have a similar function 1. Examples: The wings in a a. Bat b. Bird

D. Vestigial Structures- structures that once had a use but are no longer functional 1. Examples: a. Hipbone in Whale b. Tailbone in Humans

II. Comparison A. Complete the following chart by describing the organs as homologous, analogous, or vestigial Organ(s) Description Human “tail bone” Bat wings and Bird Wings A whale’s femur and pelvic bones Front limbs of birds, bats, dolphins Human Canine Teeth Elephant tusks and boar tusks Cow horn and deer antler Spider Fang and Snake Fang Crab Exoskeleton and Turtle Shell Human Appendix Sea horse pouch and kangaroo pouch Pelvic bone remnants in a snake Vestigial Analogous Vestigial Homologous Homologous Homologous Analogous Analogous Analogous Vestigial Analogous Vestigial