Transcript Our Understanding of the Tree of Life Continues to Change Based

Our Understanding of
the Tree of Life
Continues to Change
Based on New Data
Classifying Before
Molecular Homology
 In the late 1960’s the
kingdoms were divided into
five kingdoms. (When I was
in school, we learned about
5 kingdoms). It soon came
to be that the kingdom
monera became obsolete
and was divided into the
domains of Archea and
Eubacteria.
 Eubacteria contains most
bacteria, Archea contains
prokaryotes that live in
extreme environments, and
everything else everything
else falls into Eukarya.
Horizontal Gene Transfer
 Figure 26.1
 Horizontal gene transfer is a
process in which genes are
transferred from one
genome to another
through mechanisms
exchange of transposable
elements and plasmids,
viral infection, and the
fusion of two organisms.
 Figure 26.23