1. Speciation
Friday

2. Formation of New Species
Species = individual organisms that can interbreed and produce fertile offspring

3. Hybrid = cross between two species
Liger
Zonkey
Hybrid = cross between two species
= often produce infertile offspring (mules)

4. Speciation = formation of two species from one original species

5. Allopatric vs Sympatric Speciation “Other homeland” “Same homeland”
California Salamander Speciation

6. What type of speciation is this?

7. Hawaiian Honeycreepers
Adaptive Radiation
One ancestral species branches into many, each occupying a different NICHE

8. Reproductive Isolation - what prevents interbreeding between species?
Temporal Isolation (breeding at different times)
Prezygotic Barriers
Blocks reproduction from taking place at all
Habitat Isolation (living in different places)
Mechanical & Gamete Barriers (anatomy & egg/sperm problems)
Behavioral Isolation (mating, courtship behaviors)
Damselfly penis

9. Post-zygotic barriers
- egg and sperm produce offspring that don’t survive or are sterile

10. Rates of Speciation Slow change, small steps
Rapid change, due to a major environmental disruption

11. Is a hybrid grizzly-polar bear a “PIZZLY” or a “GROLAR BEAR”