1. Hybrid Zones
-What can happen when new or partially formed species come into contact

2. Hybrid Zones Reveal factors that lead to reproductive isolation
Happen when species have not become 100% reproductively isolated
Located where two species meet

4. 3 Possible outcomes of hybrid zones
Reinforcement of barriers
Fusion of species
Stability

5. Fusion Example

6. Rate of Speciation Does speciation happen gradually or rapidly
Punctuated Equilibrium
Gradualism
gradual accumulation of small changes over long time
rapid bursts of change mixed with long periods of little or no change

7. Gradualism vs. Punctuated Equilibrium
gradual divergence over long spans of time
assume that big changes occur as the accumulation of many small ones
Punctuated Equilibrium
rapid bursts of change
long periods of little or no change
species undergo rapid change when they first bud from parent population