Vertebrate Zoology

Vertebrate Zoology

1. ZOOLOGY

   • "The branch of biology that deals with animals and animal life. Includes: Structure, behaviour, physiology, development and classification of animals

2. NATURAL SELECTION

   • Organisms produce more offspring than ever survive
     • Organisms within species vary
       • Any variation which gives an individual a survival advantage will be passed down to the next generation (if trait is heritable)
     • Some die because those with survival advantage outcompete them
   • EVOLUTIONARY MECHANISMS
     • Mutation
     • Gene Flow
       • Movement of genes between populationa
     • Genetic Drift
       • Random changes in gene frequencies within a population
     • Recombination

3. Speed of Evolution

   • GRADUAL (Darwin and John Maynard Smith)
     • Small changes within species (microevolution)
       • evolution of new species, families etc. (macroevolution)
   • RAPID (Gould and Mayr)
     • PUNCTUATIONISTS
       • Species show little or no evolutionary change throughout history
         • When speciation does occur, it happens over a short period of time
           • Gradualism is rare in fossil records: intermediate forms are rare i.e. missing links are indeed missing