Evolution in ActionEvolution in Action

Chapter 15 Section 3Chapter 15 Section 3

Convergent EvolutionConvergent Evolution Different species become more Different species become more

similar.similar. – Example #1: Birds and batsExample #1: Birds and bats– Example #2: Dolphins and sharksExample #2: Dolphins and sharks

Divergent Evolution (Divergent Evolution (Adaptive Adaptive RadiationRadiation))

Similar species become more Similar species become more different.different. – Example: The kit fox and red foxExample: The kit fox and red fox– Example: Lions and tigersExample: Lions and tigers– Example: Turtles and tortoisesExample: Turtles and tortoises

Convergent or Divergent Convergent or Divergent Evolution?Evolution?

DivergentClosely related species evolve in different

directions

Convergent or Divergent Convergent or Divergent Evolution?Evolution?

ConvergentUnrelated species evolve similar

characteristics

Convergent or Divergent Convergent or Divergent Evolution?Evolution?

DivergentClosely related species evolve in different

directions

Convergent or Divergent Convergent or Divergent Evolution?Evolution?

ConvergentUnrelated species evolve similar

characteristics

Humans select individuals with the traits they Humans select individuals with the traits they wantwant

Then breed them to produce more individuals Then breed them to produce more individuals with those traitswith those traits

Speeds up the process of divergent evolutionSpeeds up the process of divergent evolution

Artificial SelectionArtificial Selection

When two species When two species influence each other’s influence each other’s evolutionevolution– Example:Example: Snails & Crabs Snails & Crabs– Example:Example: Plants & their Plants & their

pollinatorspollinators

– Example:Example: Shells of murex Shells of murex snailssnails evolved to become thicker and evolved to become thicker and spinier. In response, spinier. In response, crabscrabs that that eat snails evolved more eat snails evolved more powerful claws strong enough powerful claws strong enough to crack the snails’ shells. to crack the snails’ shells.

CoevolutionCoevolution

VideoVideoCoevolutionCoevolution