1. D.3.1-D.3.10

2.  D.3.1: Outline the method for dating rocks and fossils using radioisotopes, with reference to 14C and 40K.  D.3.2: Define half-life.  D.3.3: Deduce the approximate age of materials based on a simple decay curve for a radioisotope.  D.3.4: Describe the major anatomical features that define humans as primates.  D.3.5: Outline the trends illustrated by the fossils of Ardipithecus ramidus, Australopithecus including A. afarensis and A. africanus, and Homo including H. habilis, H. erectus, H. neanderthalensis and H. sapiens.  D.3.6: State that, at various stages in hominid evolution, several species may have coexisted.  D.3.7: Discuss the incompleteness of the fossil record and the resulting uncertainties about human evolution.  D.3.8: Discuss the correlation between the change in diet and increase in brain size during hominid evolution.  D.3.9: Distinguish between genetic and cultural evolution.  D.3.10: Discuss the relative importance of genetic and cultural evolution in the recent evolution of humans

3.  D.3.1: Outline the method for dating rocks and fossils using radioisotopes, with reference to 14C and 40K.  D.3.2: Define half-life.  D.3.3: Deduce the approximate age of materials based on a simple decay curve for a radioisotope.

7.  Isotopes: Version of an element with a different number of neutrons from the usual version of the same element. Example: carbon-14 or carbon-13  Radioisotopes: Isotopes that release some of their subatomic particles to reach stability. Radiation is not harmful to us but can be measured in the lab. Examples: Carbon-14 and Potassium-40

8.  Half-life is the amount of time it takes for half of the radioactive isotopes in a substance to decay. (example below is carbon-14) Number of Half-Lives Number of years which have passed % of original remaining 1573050 21146025 31719012.5 4229206.25 Etc.

9.  Curve decreases exponentially.  Theoretically the curve will never reach zero but in reality their will eventually be no more radioactive isotopes in a sample.

10.  7.5 g of this sample remain as C-14. What is the approximate age?

12.  D.3.1: 1) Get a sample of the material. 2) Measure the percentage of radioactive isotope left. 3) Use this percentage to calculate the age of the sample using the radioisotope’s halflife.  D.3.2: Half-life is the amount of time it takes for half of the radioactive isotopes in a substance to decay. (carbon-14=5730 years)  D.3.3: Deduce the approximate age of materials based on a simple decay curve for a radioisotope.

14.  D.3.4: Describe the major anatomical features that define humans as primates.

15.  Primates!

18.  Trends in primate evolution show increased hand and shoulder mobility, less hair, shortened face, increased brain to body ratio. Trends move

19. Gibbon Old World Monkeys New World Monkeys Prosimians (least related to us)

20. We share a most recent common ancestor with chimps and bonobos. Gorilla Orangutan

21.  Opposable Thumbs: Grasp objects (very important for climbing)

23.  Long thin straight fingers: Fine motor skills to manipulate objects Paw

24.  Fingernails: Primates lack claws making climbing easier. Some prosimians have modified nails that serve as a “grooming claw”

25.  Shoulder socket: Increased range of motion Freedom of movement is impossible in other animals

26.  Forward facing eyes: Allows for stereoscopic vision (3D)

27.  D.3.4: The major anatomical features that define humans as primates include:  Opposable Thumbs (Grasp objects)  Long thin straight fingers (allows fine motor skills)  Fingernails (allow for easier gripping)  Shoulder socket with increased range of motion (important for climbing)  Forward facing eyes (Allows for stereoscopic vision (3D) and depth perception)