Biolo1100
Chapter 15
How We Name Living Things
Carolus
Linnaeus
introduced a system of
classification
, or
taxonomy
, for grouping and naming similar organisms in hierarchical categories (taxa).
Using standardized
scientific
nomenclature avoids confusion that can arise from
common
names
.
Taxonomy should reflect
phylogeny
, the evolutionary history of organisms based on descent from a
common
ancestor
.
A group of organisms related by descent is called a
clade
; the evolutionary history of the
clade
is represented by a
cladogram
.
Current classification groups life into
three
domains
and
six
kingdoms.
The two prokaryotic
domains
do not constitute a
clade
: lacking a nucleus is not a
shared
character.
The prokaryote-like organelles
mitochondria
and
chloroplasts
were most likely acquired
through
endosymbiosis
.