7th Chapter 7-3 Cornell Notes “Evolution of Species”

7th Chapter 7-3 Cornell Notes Key Questions 1. How do new species form? 2. What causes the extinction of species?

Chapter 7-3 Cornell Notes: Terms habitat extinct

Chapter 7-3 Cornell Notes Paragraph 1 different environments + genetic variation + natural selection = variety of organisms; natural selection created organisms adapted to their habitats; habitat: specific environment gives what organisms need to live/grow/reproduce.

Chapter 7-3 Cornell Notes Paragraph 2 traits vary between organisms in a species; causes: DNA mutation, genes shifting during meiosis; total gene pool: sum of genetic variations in a species; the more variation in a species = the better chance of surviving environmental change.

Chapter 7-3 Cornell Notes Paragraph 3 new species can form through geographic isolation (i.e. Kaibab squirrel); new species then cannot mate with the old species successfully.

Chapter 7-3 Cornell Notes Paragraph 4 evolutionary relationships: DNA evidence (nitrogen base sequences) protein structure fossils early development (embryos gill slits) body structure (homologous bones) ;

Chapter 7-3 Cornell Notes Paragraph 5 extinct: no members of the species still alive; cause: change in environment; needs adaptation to survive changes ( to survive and reproduce); climate change may destroy habitats but adaptations can help survival.