Copy 89 Evolution Notes pt 2 90-91 Analogous, homologous, vestigial reading 92 Pg 221 Q’s and Ans.s #6-9 93 Embryology W/s

Evolution part 2

Darwin’s Argument We are the descendants of an common ancient ancestral organism.

Common descent All living organisms descend from one common ancestor

Embryology Study of gametes, embryo and fetal development.

Descent with modification Passing on traits to offspring changes them little by little

Homologous Structures Similar structures that evolved from a common ancestor. The organ or bone have similar function and make up

Analogous Structures Morphological differences in species that have the same appearance, structure or function but have evolved separately from other species They do not share common ancestor

Vestigial Organs Organs that don’t serve a major function in future descendants