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TRANSCRIPT
Public Domain
The
Cha
in o
f Bei
ng a
nd a
New
Tax
onom
y
In th
e 17
00s,
Cha
rles B
onne
t, a
Swiss
nat
ural
ist
who
stud
ied
plan
ts a
nd a
nim
als,
org
anize
d th
e na
tura
l wor
ld in
a la
dder
-like
hie
rarc
hy th
at
refle
cted
com
mon
thou
ght a
t the
tim
e.
Bonn
et b
elie
ved
that
a d
ivin
e Be
ing
crea
ted
mat
eria
ls th
at p
rogr
esse
d by
thei
r ow
n fo
rce
into
incr
easin
gly
com
plex
stag
es o
f exi
sten
ce.
Writt
en in
Fre
nch,
his
1745
illu
stra
tion
of th
e Ch
ain
of B
eing
(sho
wn
to th
e rig
ht) l
ists s
ever
al
stag
es o
f exi
sten
ce: fi
re, a
ir, w
ater
, lan
d, su
lfur,
met
als,
salts
, sto
nes,
pla
nts,
inse
cts,
shel
ls,
serp
ents
, fish
, fow
l, qu
adru
peds
, and
hum
ans.
How
ever
, oth
er e
arly
scie
ntist
s in
the
mid
17
00s w
ere
orga
nizin
g lif
e in
a w
ay th
at w
as
base
d so
lely
on
obse
rvab
le tr
aits
rath
er
than
phi
loso
phy.
The
y w
ere
conc
erne
d w
ith
crea
ting
a ne
w ta
xono
my,
or th
e de
finin
g an
d na
min
g of
gro
ups o
f org
anism
s bas
ed o
n sh
ared
cha
ract
eristi
cs.
Imag
ine
that
you
are
a b
iolo
gist
in 1
735
who
ado
pts t
his n
ew ta
xono
my.
The
car
ds
repr
esen
t the
type
s of o
rgan
isms y
ou c
ould
ha
ve o
bser
ved
at th
e tim
e. H
ow w
ould
you
gr
oup
thes
e or
gani
sms?
Use
the
card
s to
deve
lop
a ta
xono
mic
mod
el th
at o
rgan
izes
thes
e liv
ing
thin
gs.
Leeu
wen
hoek
’s “A
nim
alcu
les”
In 1
674,
Ant
onie
van
Lee
uwen
hoek
sent
to th
e Ro
yal S
ocie
ty o
f Lo
ndon
the
first
eve
r obs
erva
tions
of m
icro
scop
ic si
ngle
-cel
led
orga
nism
s. In
one
of h
is m
any
lette
rs, h
e w
rote
abo
ut th
e pl
aque
be
twee
n pe
ople
s’ te
eth:
“I th
en m
ost a
lway
s saw
, with
gre
at
won
der,
that
in th
e sa
id m
atter
th
ere
wer
e m
any
very
litt
le li
ving
an
imal
cule
s, v
ery
pretti
ly a
-mov
ing.
Th
e bi
gges
t sor
t…ha
d a
very
stro
ng
and
swift
moti
on, a
nd sh
ot th
roug
h th
e w
ater
(or s
pitt
le) l
ike
a pi
ke d
oes
thro
ugh
the
wat
er. T
he se
cond
sort
…oft
-tim
es sp
un ro
und
like
a to
p.”
Thou
gh h
is ill
ustr
ation
s (su
ch a
s the
imag
e ab
ove)
and
find
ings
w
ere
initi
ally
met
with
skep
ticism
, fur
ther
inve
stiga
tion
by
othe
r sci
entis
ts sh
owed
that
mic
roor
gani
sms d
id, i
n fa
ct, e
xist
. Su
bseq
uent
adv
ance
men
ts in
tech
nolo
gy m
ade
the
mic
rosc
ope
a co
mm
on a
nd v
alua
ble
scie
ntific
tool
.
In 1
859,
Cha
rles D
arw
in p
ublis
hed
The
Orig
in o
f Spe
cies
, whi
ch
prov
ed to
be
very
pop
ular
, tho
ugh
cont
rove
rsia
l at t
he ti
me.
Th
e bo
ok c
onta
ined
one
of t
he fi
rst a
rgum
ents
for t
he th
eory
of
evo
lutio
n w
hich
was
bac
ked
by e
vide
nce
and
prop
osed
a
mec
hani
sm fo
r the
des
cent
of a
ll liv
ing
thin
gs fr
om a
com
mon
an
cest
or.
Eval
uate
you
r pre
viou
s mod
el o
f the
tree
of l
ife
in li
ght o
f the
two
new
pie
ces o
f inf
orm
ation
: 1)
the
exist
ence
of m
icro
orga
nism
s and
2)
the
theo
ry o
f evo
lutio
n.
Can
your
mod
el e
xpla
in th
is ne
w in
form
ation
? U
se th
e ca
rds t
o re
vise
you
r mod
el a
s nec
essa
ry.
1866
A17
58 A
Public Domain
Phot
o: A
mod
el o
f an
early
mic
rosc
ope
used
by
Leeu
wen
hoek
to
mak
e th
e fir
st o
bser
vatio
ns o
f mic
roor
gani
sms..
(CC BY-SA 3.0) Jeroen Rouwkema
Édou
ard
Cha
tton
and
Prok
aryo
tes
As m
icro
scop
e te
chno
logy
impr
oved
, mor
e sc
ienti
sts s
tudi
ed
cells
and
disc
over
ed n
ew sp
ecie
s of m
icro
bes.
In 1
938,
the
Fren
ch b
iolo
gist
Édo
uard
Cha
tton
was
the
first
to c
hara
cter
ize
cells
as b
eing
with
a n
ucle
us (e
ukar
yotic
) or w
ithou
t a n
ucle
us
(pro
kary
otic)
. Ove
r the
nex
t sev
eral
yea
rs, f
urth
er in
vesti
gatio
ns
by sc
ienti
sts p
opul
arize
d Ch
atton
’s w
ork
and
defin
ed m
ore
diffe
renc
es b
etw
een
euka
ryot
es a
nd p
roka
ryot
es. T
he ta
ble
belo
w
indi
cate
s whe
ther
eac
h or
gani
sm is
a p
roka
ryot
e or
euk
aryo
te.
Revi
se y
our p
revi
ous m
odel
of t
he tr
ee o
f life
to 1
) refl
ect t
his n
ew
piec
e of
info
rmati
on a
bout
pro
kary
otic
and
euka
ryoti
c ce
lls a
nd 2
) in
corp
orat
e th
e ne
wly
disc
over
ed o
rgan
isms.
Prok
aryo
tes
(cel
ls w
ithou
t nuc
leus
)Eu
kary
otes
(cel
ls w
ith n
ucle
us)
Arc
haeo
glob
us fu
lgid
usA
cino
nyx
juba
tus
Bact
eroi
dete
s sp
p.A
garic
us b
ispo
rus
Begg
iato
a sp
p.Ba
cilla
rioph
ycea
e (c
lass
)
Borr
elia
bur
gdor
feri
Cup
ress
ocyp
aris
leyl
andi
i
Clo
strid
ium
diffi
cile
Dic
kson
ia a
ntar
ctic
a
Cya
noba
cter
ia s
pp.
Dig
itaria
eria
ntha
Des
ulfo
vibr
io d
esul
furic
ans
Equu
s qu
agga
Ente
roco
ccus
spp
.Eu
dorc
as th
omso
nii
Geo
bact
er m
etal
lired
ucen
sG
iard
ia in
testi
nalis
Hal
ofer
ax v
olca
nii
Gyp
s af
rican
us
Hal
oqua
drat
um w
alsb
yiH
omo
sapi
ens
Lact
obac
illus
spp
.Lir
iode
ndro
n tu
lipife
ra
Met
hano
brev
ibac
ter s
mith
iiPa
nthe
ra le
o
Met
hano
sarc
ina
acet
ivor
ans
Para
mec
ium
aur
elia
Met
hylo
cocc
us s
pp.
Pyru
s co
mm
unis
Rhod
opse
udon
omas
spp
.Sa
ccha
rom
yces
cer
evis
iae
Sulfo
lobu
s is
land
icus
Thio
baci
llus
spp.
Trep
onem
a pa
llidu
m
Vibr
io s
pp.
The
Dis
cove
ry o
f Arc
haea
In th
e 19
70s,
adv
ance
s in
scie
nce
and
tech
nolo
gy a
llow
ed
scie
ntist
s to
exam
ine
gene
tic in
form
ation
foun
d in
DN
A or
RN
A to
de
term
ine
the
rela
tions
hips
bet
wee
n sp
ecie
s. U
sing
the
reas
onin
g th
at g
roup
s of o
rgan
isms w
ith a
lot o
f gen
etic
info
rmati
on in
co
mm
on a
re m
ore
clos
ely
rela
ted
to e
ach
othe
r tha
n ot
hers
that
ha
ve le
ss in
com
mon
, sci
entis
ts b
egan
to re
orga
nize
the
tree
of
life.
Usin
g th
e sim
ulat
ed D
NA
sequ
ence
s det
erm
ine
how
the
orga
nism
s ar
e re
late
d. O
bser
ve h
ow th
is ne
w in
form
ation
influ
ence
s the
tree
of
life
mod
el.
1969
A19
90 A
1758 B
AnimalsAnimals PlantsPlants
© P
roje
ct N
EURO
N, U
nive
rsity
of I
llino
is
Illustrated interpretation of Linnaeus’ model18
66 B
Ani
mal
sPr
otis
ts
Monera
Plan
ts
© P
roje
ct N
EURO
N, U
nive
rsity
of I
llino
is
Illus
trate
d in
terp
reta
tion
of H
aeck
el’s
mod
el
1969
B
Prot
ists
Mon
era
Plan
tsFu
ngi
Ani
mal
s
Euka
ryot
es
Prok
aryo
tes
© Project NEURON, University of Illinois
Illus
trate
d in
terp
reta
tion
of W
hitta
ker’s
mod
el
ArchaeaBa
cter
ia
OriginOrigin
Eukaryotes
AnimalsFungi Plants Protists
© P
roje
ct N
EURO
N, U
nive
rsity
of I
llino
is
Illustrated interpretation of Woese’s model1990 B
Publ
ic D
omai
nPu
blic
Dom
ain
Publ
ic D
omai
n
Carolus Linnaeus’ Systema Naturae
Carl Linnaeus is the founder of modern taxonomy, the naming and classification of life forms. He started using two-part names for living things, a method that is still used today. For example, he used the genus and species name of Panthera leo for the lion.
Linnaeus’ interests in biology originated with plants. Growing up, his father would show Linnaeus flowers in the garden and tell him their names. As an adult, Linnaeus continued to study plants and animals on expeditions across Europe before publishing his work in several books.
In his book Systema Naturae (Latin for “The Systems of Nature”), Linnaeus classified over 12,000 plants and animals. During his lifetime, the contents were constantly being updated and revised based on new knowledge. For instance, whales were originally classified as fish in the first edition (1735), but in the tenth and definitive edition (1758), they were reclassified as mammals.
Linnaeus arranged life into two main categories, called “kingdoms”: plants and animals. Plants were grouped into 24 classes based on their reproductive structures and included “true” plants as well as fungi, algae, and lichen. His classification of animals included subgroups of mammals, birds, amphibians, fish, insects, and “vermes,” or all other invertebrates that were not insects, such as worms, slugs and clams.
Below is a table from an earlier edition of Systema Naturae showing some groups from the kingdom “Animale.” Do you recognize any of the organism names?
1758 B
Public Domain
Public Domain
Erns
t Hae
ckel
Erns
t Hae
ckel
was
form
ally
trai
ned
as a
med
ical
doc
tor b
efor
e be
com
ing
a zo
olog
ist. D
urin
g hi
s life
, inc
ludi
ng th
e tim
e he
was
a p
rofe
ssor
at t
he
Uni
vers
ity o
f Jen
a, G
erm
any,
he st
udie
d m
any
inve
rteb
rate
gro
ups s
uch
as sp
onge
s and
radi
olar
ians
, tiny
zoop
lank
ton
with
min
eral
skel
eton
s.
Haec
kel w
as a
n ac
com
plish
ed il
lust
rato
r and
mad
e ex
tens
ive
jour
neys
ar
ound
the
wor
ld, n
amin
g th
ousa
nds o
f new
spec
ies i
n hi
s life
time.
Haec
kel’s
con
trib
ution
s to
the
disc
over
y of
new
spec
ies a
nd th
e or
gani
zatio
n of
life
pro
ved
influ
entia
l. In
his
book
Gen
erel
le M
orph
olog
ie
der O
rgan
ismen
(Ger
man
for “
Gene
ral m
orph
olog
y of
org
anism
s”)
publ
ished
in 1
866,
Hae
ckel
dep
icte
d a
tree
(see
illu
stra
tion)
with
thre
e ki
ngdo
ms:
Pla
ntae
, Ani
mal
ia, a
nd P
rotis
ta. A
t the
tim
e, P
rotis
ta in
clud
ed
all m
icro
scop
ic o
rgan
isms.
At t
he o
rigin
of t
he tr
ee h
e pu
t “M
oner
es”
or M
oner
a, a
gro
up o
f sim
ple
mic
robe
s poo
rly u
nder
stoo
d at
the
time.
Hae
ckel
thou
ght t
hese
org
anism
s wer
e sim
ilar t
o th
e fir
st li
ving
or
gani
sms f
rom
whi
ch
all l
ife e
volv
ed.
1866
B
Whi
ttake
r, R.
H. (
1969
)©
Nat
iona
l Aca
dem
y of
Sci
ence
s.
Robert H. Whittaker
In 1969, Robert Whittaker published a scientific paper in which he proposed a new five-kingdom model of the tree of life. In his model, Whittaker incorporated work of Chatton and other scientists who distinguished prokaryotes from eukaryotes. He also established a new kingdom for fungi, which had mostly been grouped with plants in the past. The separation of fungi was mostly based on the evidence that fungi consume decaying or dead matter whereas plants produce their own food.
In Whittaker’s model (shown below), there were five kingdoms: Monera (prokaryotic organisms), Protista (eukaryotic unicellular organisms), Plantae, Animalia, and Fungi (all eukaryotic multicellular organisms). As seen in his illustration, the arrangement suggested that some kingdoms, such as Monera and Protista, contained present-day species as well as the ancestors of other kingdoms. The arrows in the bottom right also indicate how he organized species based on whether they photosynthesize, absorb, or ingest food.
1969 B
Woe
se, C
.R.,
Kan
dler
, O. &
Whe
elis,
M.L
. (19
90)
Carl Woese
Carl Woese, a scientist at the University of Illinois, was one of the first to use molecular data to investigate the evolutionary relationships of organisms. The illustration below is from a 1990 publication he wrote with colleagues, titled “Towards a natural system of organisms: Proposal for domains Archaea, Bacteria, and Eucarya.” A “domain” is a taxonomic group even larger than a kingdom. There were now six kingdoms in the new model, revised from Whittaker’s five kingdom model. The Plantae, Animalia, Protista, and Fungi kingdoms were grouped in the Eukarya domain, and the Bacteria and Archaea domains contained the Bacteria and Archaea kingdoms, respectively.
In previous models of the tree of life, archaea had been classified with bacteria, and both under the category of monera. Although archaea are visually similar to bacteria, studies indicate that archaea have genes and cellular functions more similar to eukaryotes. The earliest discovered archaea were in extreme environments such as volcanic hot springs and salt lakes, but since then they have also been found in places such as soils and human intestines. Archaea species derive energy from compounds ranging from sugars to metal ions, and they have unique components in their cell membranes not found in the other domains.
1990 B
© 2
004
Don
Ham
erm
an, U
nive
rsity
of I
llino
is