Patterns of speciation- Allopatric, Sympatric, Parapatric and Peripatric with examples Ecology and Evolution

1. Anagenesis
Original species is transformed
into a different species over
many generations
Patterns of Speciation
Cladogenesis
Pattern of branching in which an ancestral
species gives rise to two or more new
species
1
klados=branch
Common
Branching evolution
Promotes biological
diversity -
No. Of species
Ana= new genos= race
Rare
Phyletic evolution
One taxon replaces the
other

2. Types of Speciation
Allopatric Speciation
2
Original
species
Geographical
Barrier
New
species

3. Allopatric
● Grand Canyon
● Kaibab and Abert squirrels
3
Alios= other

4. Types of Speciation
Allopatric Speciation
4
Sympatric Speciation
Original
species
Genetic
polymorphism
New
species

5. SYMPATRIC
● Hawthorn flies and
apple flies
● Genetically Isolated
while in the same
place
5
sym=togather

6. Types of Speciation
Allopatric Speciation
6
Sympatric SpeciationParapatric Speciation
Original
species
New niche
formed
New
species
Adjacent
niche

7. Parapatric
● Grass growing in areas
contaminated with heavy
metals
● Not reproductively
isolated
● Reduced gene flow
7
Anthoxanthum odoratum

8. Types of Speciation
Allopatric Speciation
8
Sympatric Speciation Parapatric Speciation Peripatric Speciation
Original
species
New
species
New niche
formed
Isolated
niche

9. Peripatric
● Mainland Vs Island flies
● Reproductively Isolated
● “Founder effect”
9
peri= periphery