1. 14.1

2. I can recognize patterns of change in populations over time I can give examples of evidence that supports evolution I can describe fossils of early human ancestors

3. The changes in a population over time An organism changes as it grows and develops, but this is NOT evolution Evolution occurs within populations As organisms in a population die off, new organisms are born into it

4. Levels of Organization Ecosystem Community Population Organism Biosphere

5. Genes determine the traits of all living things Evolution involves changes in a population’s gene pool Genes can be changed by radiation, chemicals in the environment, and if they are copied incorrectly Mutations in gametes do not affect the parent, but instead they get passed on to the offspring

6. Mutations can cause harmful changes in traits A lethal mutation is one that results in an organism’s death Most mutations, though, are favorable and are passed on to offspring As the mutation is passed on to future generations, it becomes more and more common with the population

7. If a population’s environment changes, members of the population that have certain favorable traits maybe more likely to survive Evolution occurs slowly as these favorable traits are passed on from one generation to the next

8. A change in the environment may split a population into two isolated groups A large river, or canyon may form and divide a population The single population now becomes two populations that have no contact with each other Different mutations can occur which result in different genes

9. Sometimes a population can be divided if organisms move out of the area For example, organisms may travel from the mainland to a neighboring island Over time, if enough change occurs, the island population may evolve into a new species

10. Evolution Lethal Mutation Geographic Isolation Self-Check Questions #1-5 pg. 316 COMPLETE SENTENCES

11. 14.2

12. Fossils are the remains or traces of organisms that lived in the past Fossils are found in rock, tree sap, and other materials Fossil comes from the Latin word fossilis, meaning “dug up”

13. Bones and teeth can remain as fossils for millions of years Fossils can be found in mud and bits or rock, called sediment, at the bottom of water Over time, layers of sediment harden into rock and leave a type of fossil called a mold Animals and insects have also been found in hardened tree sap and frozen in ice

14. Paleontologists are scientists who study life in the past, or fossils Their findings have formed a fossil record, which is a history of life on Earth, based on fossils that have been discovered Fossil records also show how organisms have changed over time Life on Earth dates back 3.5 billion years (geologic time scale) pg. 319

15. Scientists can tell how old a fossil is by comparing its location in rock Fossils in lower layers of rock are older than fossils in upper layers of rock Scientists can also use radioactive materials to date fossils Radioactive materials give off energy as they change to another substance over time

16. When a species disappears, it is said to be extinct A fossil record will show when different species lived and then disappeared from Earth As species become extinct, new species appear Mass extinctions (large numbers of species became extinct) are caused by major changes in environment

17. Fossils show how groups of organisms have changed over time Horses and humans are examples (pg. 321)

18. Scientists learn more about fossils by comparing them to living organisms The look for similar structures, such as teeth and bones Fossils have proven that certain species have evolved: Certain fish have evolved into amphibians Reptiles have evolved into mammals Some reptiles have evolved into birds

19. Fossil Sediment Fossil Record Extinct Self-Check Questions #1-5 pg. 323 COMPLETE SENTENCES