Anagenesis and Cladogenesis

There are two types of change. These are depicted here as anagenesis and cladogenesis. The latter, of course, implies the process of speciation. The former relates to changes over time in a species.

There are three terms that you should know relative to evolution. These are: Divergent Evolution, Covergent Evolution, and Parallel Evolution. The keys to understanding the differences between these terms is to contrast ancestry, adaptations, and eventual forms. If you do this, you will find these terms easy to understand.

DIVERGENT EVOLUTION

Evolution of DIFFERENT adaptive traits in forms that were once related but then diverged, developing along different lines.

In terms of ancestry, adaptation and form:

• there is similar ancestry,
• different adaptations and
• resulting different forms.

CONVERGENT EVOLUTION

Evolution of similar adaptive traits

In terms of ancestry, adaptation and form - consider convergent evolution to reflect

• different ancestries,
• similar adaptations and
• resulting similar forms.

PARALLEL EVOLUTION

Evolution of similar adaptive traits in forms that were once related but then diverged, developing along similar lines.

In terms of ancestry, adaptation and form: there is

• similar ancestry,
• similar adaptations and
• resulting similar forms.