LECTURE 1:  LINEAGES, POPULATIONS AND GENETIC VARIATION

I.  Meet your ancestors

     A.  All organisms are descended from a single common ancestral species that lived 3.5 - 3.8 billion years ago.

     B.  Evidence for common descent from a single ancestor.
 

II.  Implications of single common ancestor.

     A.  Current Organismal Diversity

     B.  Common ancestor of this diversity implies operation of two primary evolutionary processes:

          1.  PHYLETIC EVOLUTION

          2.  LINEAGE SPLITTING

III.  Definitions and Terms

     A.  POPULATION:

     B.  LINEAGE:

     C.  GENEOLOGY

     D.  POPULATION
           .

IV.  Phyletic Evolution

     A.  Causes of differences between ancestors and descendents

          1.  Environmental Change

          2.  Genetic Change

     B.  Definition of Evolution
.

V.  Lineage Splitting

     A.  Lineage divergence

     B.  Evolution of Reproductive Isolation
 
 
 

VI.  Distinguishing between Environmental and Genetic causes of change in average character state
        within a lineage

          A.  Common Garden Experiments

          B.  Example:  Experiment of Clausen, Keck and Hiesey on Potentilla glandulosa
 

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