Read Chapter 15 in the text and answer the following questions.  Open book, work alone.

1. (2) The biological species concept has become part of the modern synthesis or classical theory of evolution.  What is characteristic of biological species?
 
 
 
 
 

2. (2) How is the phylogenetic concept of species different from the biological species concept?
 
 
 
 
 
 

3. (2) The classical theory of speciation is based on the allopatric model, developed by whom?  Give an example to illustrate how this works.
 
 
 
 
 

4. (2) Speciation can also take place without allopatric separation.  Give an example to illustrate how this can happen.
 
 
 
 
 
 

5. (2) When populations become isolated, genetic differences can be accentuated by natural selection, which tends to maintain reproductive isolation among the isolated populations.  Give an example of how this can happen.