Do Now What does it mean to evolve

Do Now What does it mean to evolve? Provide an example based on the modern theory of evolution.

Convergent Evolution Selective pressure

Convergent Evolution The process that occurs when organisms that are not closely related, independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.

Similar traits independently evolve in unrelated species

Convergent Evolution leads to… Analogous structures: Body parts that are similar in structure and functions that have no anatomical or embryological similarities Ex. Bird wings and insect wings

Divergent Evolution When related species become more and more different in response to different environments

Divergent Evolution leads to… Homologous Structures: Body parts that are alike because of a common ancestor These structures may serve the same or different functions Ex. Forelimbs

Homologous structures

Coevolution

Coevolution The change in the evolution of one species in response to a change in another species. Ex: Honeybees become dependent on flowers, and flowers become dependent on honeybees for survival.

Vestigial structures Organs that were useful for an ancestors, but no longer useful in the modern day species. Ex. Appendix Jean Baptiste Lamarck discovered and named vestigial structures