15.1/15.2

definition of a species as a population or group of populations whose members can breed with one another in nature and produce fertile offspring 

• biological species concept 
• macroevolution 
• speciation 
• reproductive isolation 

major biological changes evident in the fossil record 

• speciation 
• biological species concept 
• macroevolution  
• reproductive isolation  

formation of new species 

• macroevolution 
• speciation 
• reproductive isolation 
• biological species concept 

condition in which a reproductive barrier keeps two species from interbreeding 

• biological species concept  
• macroevolution  
• speciation  
• reproductive isolation  

separation of populations as a result of geographic change or migration to geographically isolated place 

• geographic isolation 
• adaptive radiation 
• punctuated equilibrium 
• embryology 

evolution from a common ancestor of many species adapted to diverse environments 

• geographic isolation  
• adaptive radiation  
• punctuated equilibrium  
• embryology  

evolutionary model suggesting species often diverge in spurts of relatively rapid change, followed by long periods of little change 

• geographic isolation 
• adaptive radiation 
• punctuated equilibrium   
• embryology   

study of multicellular organisms as they develop from fertilized eggs to fully formed organisms 

• geographic isolation  
• adaptive radiation   
• punctuated equilibrium  
• embryology