1. Life As We Know It Genetics and the Origins of Humankind

2. Humble Beginnings Life (4000 mya) Bacteria (3900 mya) Algae (1600 mya) Plants (1300 mya) Vertebrates (510 mya) Mammals (114 mya)

3. Hominids Primates evolved ~95 mya Great Rift Valley:  separates African animal populations  diverse ecological conditions Hominids diverged from Apes on border of forested and savanna environments Homo sapiens sapiens ~150,000 ya

4. Inefficient means of travel (except in savanna) Knuckle-walking Adapted for arboreal lifestyle Predator avoidance Availability of hands Cooling and birthing Bipedalism

5. Rapid encephalisation of the brain:  1 to 3 lb. brain in only 2 m years Machiavellian intelligence Climate change Ballistic hunting Language and group size Sexual selection Origins of the Mind

6. DNA & base pairs:  Adenine & Thymine, Cytosine & Guanine  Shared among all life Genes are sequences of DNA  Build specific proteins  Different forms of a particular gene are called alleles Genetics: The Machine at Work

7. Chromosomes Strings of genes 23 pairs:  23 paternal copies  23 maternal copies Ordered by size (imperfectly)

8. Sex Chromosomes X chromosome:  All humans have at least 1 copy  Females have 2 (homogametic) Y chromosome:  In humans, only males have a copy  Males have 1 X and 1 Y (heterogametic)  Little genetic information, “SRY”

9. Mendelian Heredity Chromosomes separate (segregate) during gamete formation Dominant & recessive genes Exception: Mitochondrial DNA

10. Mathematics of Inheritance Punnett squares: Female gametes Male gametes T T T Female gametes Male gametes T T t tt TT tt Tt

11. The Wrap-Up Evolution of life on Earth Great Rift Valley Arboreal & savanna environments Bipedalism Encephalisation & origins of the mind DNA, genes, chromosomes (incl. sex chromosomes) Mendelian heredity & Punnett squares

12. Things to Come Problems of survival:  Food acquisition & selection  Habitat & environmental preferences  Predators & environmental dangers  Senescence