THE ORIGIN OF SPECIES

What is a species?

Morphological Species Concept - used in taxonomy and paleontology

Biological Species Concept

Two Patterns of speciation - Fig. 24.1

• Anagenesis
• Cladogenesis

REPRODUCTIVE ISOLATION.
Isolating Mechanisms - Fig. 24.5- a table explaining these mechanisms

     Prezygotic

- Habitat
- Behavioral - Fig. 24.3
- Temporal

- Mechanical   beetle and genitalia
- Gametic

 

      Postzygotic

 

- Reduced hybrid viability
- Reduced hybrid fertility (Sterility)
- Hybrid Breakdown

SPECIATION MODELS - A comparison - Fig. 24.6

   - Allopatric speciation. - Fig. 24.7 Geographic isolation - Fig. 24.8

          ADAPTIVE RADIATION - Fig. 24.11 An example - Fig. 1.17b
   - Sympatric Speciation.

Polyploidy

     Autopolyploidy. - Fig. 24.13

     Allopolyploidy. - Fig. 24.15

TEMPORAL ASPECTS OF EVOLUTION (Fig 24.17)

    - Gradualism

    - Punctuated Equilibrium

Micro evolution vs. MACROEVOLUTION          Macroevolution - the Movie!

- Modified versions of older structures - mollusk eyes - Fig. 24.18

- Allometric growth - Fig. 24.19a

- Paedomorphosis  - Fig. 24.19b         Paedomorphosis - the Movie!

A review of evolution can be found here. Be sure you are familiar with these terms and concepts, which you should have learned in Bio 212. I will assume that you are.