1. EVOLUTION natural selection UNIT 9 BIOLOGY

2. Fossils CAST MOLD

3. Geological History

4. Lamarck Acquired Traits Lamarck proposed that species acquired traits in response to the environment. The acquired traits were then passed on to the offspring.

5. Darwin Darwin had TWO theories: 1)Descent with Modification 2)Modification by Natural Selection Descent with Modification: Modern species are descended from older species in the fossil record. Modification by Natural Selection: The environment “ selects ” traits in species that will enable them to survive.

6. Lamarck v Darwin

7. Homologous/Analogous Homologous structures: They look alike and serve the same purpose. Analogous structures: Serve the same purpose but are of different in structure.

8. Vestigial Structures Structures that were useful to an ancestor, but seem to serve no useful function in the current species.

9. Embryological Development Top Row: a Fish Embryo Second Row: a Chick Embryo Third Row: a Pig Embryo Bottom Row: a Human Embryo

10. Coevolution Two or more species closely dependent on each other change together to rely on each other even more. Predator/prey; Parasite/host Examples of Coevolution: Monarch butterfly eats poisonous milkweed giving the monarch protection against predators. Acacia tree has hollow thorns for eggs, give nectar to ants who defend the tree against herbivores.

11. Extreme Coevolution Anoura fistulata, a bat from the Ecuadorian Andes, dives for nectar inside a Centropogon nigricans flower.

12. Extreme Coevolution The bat species: Anoura fistulata has the longest tongue compared to the size of its body in the world. The A. fistulata has evolved together with one single species of flower: Centropogon nigricans These two species are found only in the Ecuadorian cloud-forests

13. Convergent Evolution The environment selects similar phenotypes for unrelated species.

14. Divergent Evolution Two or more closely related species become more different from each other over time.  Species changes are almost always in response to differing habitats. Two Kinds of Divergent Evolution: Adaptive radiation – many related species evolve from one common ancestor Ex: Galapagos Finches differentiated due to different habitats and food sources. Artificial Selection – man selects certain traits that are desired and breeds for those traits. Ex: Pure-bred dogs, hybrid tomatoes, corn, pure-bred cattle

15. Divergent Evolution Two Kinds of Divergent Evolution: Adaptive radiation – many related species evolve from one common ancestor Ex: Galapagos Finches differentiated due to different habitats and food sources. CLOSE

16. Divergent Evolution Artificial Selection – man selects certain traits that are desired and breeds for those traits. Ex: Pure-bred dogs, hybrid tomatoes, seedless watermelon,