Patterns of Evolution:
Convergent Evolution,
Coevolution &
Divergent Evolution
Convergent Evolution
 Occurs when different organisms that live in
similar environments become more alike in
appearance and behaviour.
 The environment selects similar adaptations
in unrelated species.
 Organisms develop analogous structures
(same function, but different origins).
 Examples: - Bird wings/insect wings
- Shark fins/dolphin fins
More examples:
Placental Mammals: top row
Marsupial Mammals: bottom row
Coevolution
 When two species evolve together.
 There is a mutual evolutionary influence
between two species.
 The species have a symbiotic relationship
(interaction between members of two
populations).
 Example: - Birds and flowers
Divergent Evolution
 The process by which an ancestral species
gives rise to a number of new species that
are adapted to different environmental
conditions and are less alike.
 Often occurs when a species colonizes a
new environment.
 Also known as adaptive radiation.
 Examples: - Darwin’s Finches.
- Brown bears and polar bears
Divergent Evolution