Speciation I. Microevolution and
macroevolutionII. Patterns of descentIII. Species concepts
A. Biological speciesB. Ecological speciesC. Morphological speciesD. Phylogenetic species
IV. Barriers that lead to speciation
A. PrezygoticB. Postzygotic
V. Modes of speciationA. Allopatric speciationB. Sympatric speciation
III. Species conceptsA. Biological species
C. Morphological species
‘Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from each other.’ Mayr
B. Ecological species
niche
Reproductive isolating mechanisms (RIMs)
D. Phylogenetic species
• Molecular clocks
• A species consists of a population or group of populations that share a common evolutionary fate through time.
Fossil record
• promiscuous
• ecotypes• fossil record
III. Species conceptsProblems with definitions
• asexual species
Link
• convergent evolution
IV. Barriers that lead to speciationA. Prezygotic barriers
1. Habitat isolation
2. Behavioral isolation
• sexual selection
Sage grouse Songbirds
3. Temporal isolation
4. Anatomical isolation
5. Gametic isolation
• diurnal, nocturnal, crepuscular
A. Prezygotic barriers
Evo-devo Genes
HOX genes
Gene regulation