Theory of Evolution
part III

Case study: Anole lizards of the
Caribbean
ongoing examples of evolution
among living organisms can be
observed, recorded and tested
In convergent evolution organisms
that are not closely related
resemble each other because they
have responded to similar
environments

Natural selection of the Anole
Twig dwelling species evolved independently (not
related) on each island -convergent evolution
each island had closely related twig dwelling, trunk
dwelling and ground dwelling forms - divergent evolution

Adaptive Radiation
A new population in a new
environment ( like an island) will
undergo divergence until populations
fill the various parts (niches) of the
environment

Artificial Selection
Dog breeding was an example used by
Darwin to explain the idea of selection
DNA analysis today supports the idea
that humans first selected domestic dogs
from a wolf population about 15,000
years ago.

Coevolution
When two or more species have evolved
adaptations to each other’s influence.
Examples: bacteria evolving a capsule to
resist your immune system
antibiotic resistance
Animal toxins and prey resistance