3. Evolution = process by which modern organisms have descended from ancient organisms. A change in populations over long periods of time. Scientific Theory = well-supported, testable explanation of phenomena that have occurred in the natural world.

4. **In 1831, Darwin set sail from England aboard the H.M.S. Beagle for a voyage around the world. **During his travels, Darwin made numerous observations and collected evidence that led him to propose a hypothesis about the way life changes over time. (natural selection)

5. Process by which individuals who are better adapted for their environment survive and reproduce successfully. In the Galapagos Darwin notices that there were variations among members of the same species. Example: Finches, Giant Tortoise

6. Three species of tortoises each inhabit a different island in the Galápagos Testudo abingdonii, inhabits the Pinta island and has a longer neck to reach vegetation Pinta Island Intermediate shell Pinta Isabela Island Dome-shaped shell Hood Island Saddle- backed shell Hood Floreana Santa Fe Santa Cruz James Marchena Fernandina Isab ela Tower

7. Fitness: the ability for an organism to survive and reproduce in its environment. It’s a result of adaptation. Adaptation: any inherited characteristic that increases an organism’s chances for survival. Hummingbirds have adapted to their environment in two ways: 1.Very fast flight to keep them steady. 2.Long beak and tongue to reach into flowers and extract nectar.

8. The evolution of the peppered moth over the last two hundred years has been studied in detail. Originally, the vast majority of peppered moths had light coloration, which effectively camouflaged them against the light-colored trees and lichens upon which they rested. However, due to widespread pollution during the Industrial Revolution in England, many of the lichens died out, and the trees which peppered moths rested on became blackened by soot, causing most of the light- colored moths, to die off due to predation

9. The Peppered Moth Scenario is an example of ______. a.Transcription b.Natural Selection c.Artificial Selection d.Translation

10. 1 2 4 6 8 10 12 14 16 18 A small Texas town recorded the above mosquito data every week for a 5-month period of time. During this time insecticide was sprayed to try and reduce the large number of mosquitoes. What is the best explanation for the decreased effectiveness of the insecticide over time? A Mosquitoes that were resistant to the insecticide lived and produced offspring. B The insecticide was sprayed only once. C The insecticide harmed the mosquito’s DNA causing mutations that prevented reproduction. D The temperature decreased the effectiveness of the insecticide.

11. Evidence of evolution.

12. Evidence that living things have been evolving for millions of years includes: The fossil record Some of the fossils resembled organisms that were still alive. Others looked completely unlike any creature he had ever seen. Homologous, analogous, and vestigial structures Embryology Geographic distribution of living things Biochemistry

13. Water carries small rock particles to lakes and seas. Dead organisms are buried by layers of sediment, which forms new rock. The preserved remains may later be discovered and studied. What are fossils? Remains of once living organisms Like the hard parts of organisms (i.e. bones), impressions, or casts.

14. Portrayed by remains of ancient life forms. When fossils are discovered they can be added to the fossil record based on age and similarities. Found mainly in Sedimentary Rock

15. Similar in structure but functions differently Examples: flying, swimming, grasping etc.

16. Structures that have a similar function, but different structures. Example: Butterfly and bird both use their wings for flying, but wings are structured differently, one has bones, one has network of veins.

17. Structures that serve no useful purpose in an organism. In whales, there is a vestigial pelvis and femur. In horses, there is a vestigial toe. In snakes, there are vestigial hips Can you name any vestigial structures in humans?

19. Similarities in Embryology In their early stages of development,, development, chickens, turtles and rats look similar, providing evidence that they shared a that they shared a common ancestor.

20. Based on modern knowledge of genetics, we now know that natural selection is dependent on genetic variation within the gene pool. Gene Pool: consists of all the genes including all the different alleles that are present in a population. A population is a group of individuals that inhabit the same area.

21. Closely related species share common base sequences Biochemistry: DNA and Proteins

23. When two populations of a species becomes separated by geographic barriers such as rivers or mountain ranges resulting in the formation of 2 separate gene pools. Ex: Abert Squirrels vs. Kaibab Squirrels.

24. a change in allele frequencies that occur in small populations. These changes are associated with random events. founder effect small group splinters off & starts a new colony bottleneck some factor (disaster) reduces population to small number & then population recovers & expands again

25. diverse population  “catastrophic event” (hunting, earthquake, volcanic eruption, etc.  small % of the original population remains & repopulates  less diverse population Bottleneck Effect Bottleneck Effect

26. When large population is drastically reduced by a disaster famine, natural disaster, loss of habitat… loss of variation by chance event alleles lost from gene pool not due to fitness narrows the gene pool

27. All cheetahs share a small number of alleles less than 1% diversity as if all cheetahs are identical twins 2 bottlenecks 10,000 years ago Ice Age last 100 years poaching & loss of habitat

28. Small population gets separated by chance (storm, earthquake, etc.) Develop different adaptations over many generations If they come in contact later, they are too different to interbreed Ex. Galapagos finches fly to nearby island

29. When a new population is started by only a few individuals some rare alleles may be at high frequency; others may be missing skew the gene pool of new population human populations that started from small group of colonists example: colonization of New World

30. Genetic Flow: the transfer of genes or alleles from one population to another.

31. Movement of individuals & alleles in & out of populations seed & pollen distribution by wind & insect migration of animals sub-populations may have different allele frequencies causes genetic mixing across regions reduce differences between populations

32. Gene flow in human populations is increasing today transferring alleles between populations Are we moving towards a blended world?