Review: What is Biodiversity? The diversity of life Examples: There are over 10,000 species of birds known in the world, 900,000 different kinds of living insects, about 280 known living species of monkey and about 78 species of whales, dolphins, and porpoises.

2. What were early beliefs on how so many different species developed? Before the 1800s, most people believed that species were unchanging. In the early 1800s, a scientist by the name of Lamarck suggested that species were not constant. He believed that new species evolved from preexisting species. This was a big deal!!!!

3. What were Lamarck’s 2 Principles? 1) The more an animal uses a body part, the stronger and bigger it becomes. If the body part is not used, it becomes smaller and weaker. This is called the law of use and disuse. 2) These changes in body parts could be passed from parent to offspring. This is called the theory of the inheritance of acquired characteristics. Right or Wrong?

4. Who is Charles Darwin? A Naturalist that Sailed around the world from 1831-1836 studying nature and collecting organisms.

5. What important observations did Darwin Make? 1.The diversity of living species was far greater than anyone had previously known!! 2. Organisms had unique adaptations 3. Organisms with unique adaptations resembled other similar organisms. 4. Fossils of extinct species resembled many living species.

What important observations did Darwin Make Continued? 5. Organisms competed for resources like food, shelter, and mates. 6. These observations led him to the idea of natural selection and helped him develop the theory of evolution!!

6. What is Natural Selection? Due to genetic differences (mutations) , some organisms will have a better chance at surviving long enough to reproduce than others. These beneficial traits will be passed down through the generations, producing change in a species over time.

Natural Selection Continued: The traits that help an organism survive in a particular environment are “selected” by pressures in that environment.

7. What are Selection Pressures? Limiting Factors, or environmental variables, that make it harder for individuals to survive. Examples: Over population of a species, limited food/space, disease, extreme environmental conditions, competition for mating rights. Individuals that are better equipped to deal with these selection pressures are the ones that will live long enough to reproduce.

8. Natural Selection Video: Take 5 movie notes as you watch the movie clip on Natural Selection. http://www.youtube.com/watch?v=0SCjhI86grU

Find a partner NEARBY and discuss the following questions: 1. Do you believe in natural selection? 2. Do you believe that organisms can change over time?

9. How does Natural Selection lead to Species Fitness? Overtime, natural selection results in changes in the inherited characteristics of a population. These changes increase a species fitness (survival rate)

10. What is “Survival of the Fittest?” Life is a struggle in which only those organisms best adapted (most fit) to existing conditions are able to survive and reproduce.

11. How does Natural Selection explain Descent with Modification. Each living species has descended with changes from other species over time.

12. How does natural Selection help explain evolution? It explains how and why species change over time.

13. What is Evolution? Evolution: gradual change over time Geological Evolution: Continuous change in the Earth over the last 4.5 billion years Organic Evolution: Changes in species over time. Modern Species descended from ancient species through natural selection.

14. Evolution Movie Take 5 Movie Notes: http://www.youtube.com/watch?v=GhHOjC4oxh8

Darwins 6 main points Quiz: Read the descriptions on your paper and use the word bank to try and fill in the correct answers: Natural Selection, Speciation, Adaptations, Variation, Overproduction, Competition

15. Darwin’s 6 main points: 1) Overproduction: Species produce far more offspring than needed to maintain a population. But, because only a small fraction survive to adulthood, population numbers remain relatively constant. 2) Competition: Only a small number of offspring survive because organisms must compete for a limited amount of resources.

Darwin’s 6 Main Points 3) Variations: Not all members of a population are exactly the same. Some are bigger, faster, stronger, than others. This is due to genetic differences among members. 4) Adaptations: These genetic differences between members of a population provide some organisms with a better chance at winning the competitions for these limited resources.

Darwin’s 6 Main Points 5) Natural Selection: Nature “selects” which organisms are best suited for survival and reproduction. Those with unfavorable traits don’t survive long enough to reproduce. 6) Speciation: Overtime, only those species with favorable traits will survive long enough to reproduce. They will pass these traits on to their offspring, who are will probably have the same favorable traits. Hence, a species emerges.

7. Evolution is a Theory – Just like Gravity! Evolution is a well supported explanation of phenomena that have occurred in the natural world A theory in science is a well tested hypothesis, not just a guess

What is Artificial Selection? nature provides variation, humans select variations that are useful. Example - a farmer breeds only his best livestock

13. Evidence of Evolution Fossil Record Geographic Distribution of Living Species Homologous Body structures Similarities in Embryology

Evidence of Evolution Fossil Record provides evidence that living things have evolved Fossils show the history of life on earth and how different groups of organisms have changed over time

Relative vs. Absolute Dating

Relative Dating Can determine a fossil’s relative age Performed by estimating fossil age compared with that of other fossils Drawbacks – provides no info about age in years

Absolute dating Can determine the absolute age in numbers Is performed by radioactive dating – based on the amount of remaining radioactive isotopes remain Drawbacks - part of the fossil is destroyed during the test

Carbon-14 Dating

Fossil Formation SG

Primate Fossils Australopithecus Homo erectus Homo sapien

Primate Brain Capacity

Primate Bone structure

Human Relatives

Australopithecus afarensis

Homo habilis = handy human 1.5 to 2 mya Homo erectus 1.6 mya Homo habilis = handy human 1.5 to 2 mya bipedal

Cro-Magnon 35,000 to 40,000 ya Neanderthals 35,000 to 100,000 ya http://www.culture.gouv.fr/culture/arcnat/chauvet/en/

(fully modern fossils 100,000 ya) Modern Homo sapien (fully modern fossils 100,000 ya)

13. Evidence of Evolution Geographic Distribution of Living Species Similar animals in different locations were the product of different lines of descent

13. Evidence of Evolution Homologous Body Structures Turtle Homologous Body Structures Structures that have different mature forms but develop from the same embryonic tissues e.g. Wing of bat, human arm, leg of turtle Alligator Bird

Homologous Body Structures

Vestigial Organs traces of homologous organs in other species Organ that serves no useful function e.g. Appendix

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

Embryological development