DOI 10.1126science.1184944, 195 (2010);328 Science et .docx

DOI: 10.1126/science.1184944
, 195 (2010);328 Science
et al.Lee R. Berger
from South Africa
-Like AustralopithHomo: A New Species of Australopithecus
sediba
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Australopithecus sediba: A New
Species of Homo-Like Australopith
from South Africa
Lee R. Berger,1,2* Darryl J. de Ruiter,3,1 Steven E.
Churchill,4,1 Peter Schmid,5,1
Kristian J. Carlson,1,6 Paul H. G. M. Dirks,2,7 Job M. Kibii1

Despite a rich African Plio-Pleistocene hominin fossil record,
the ancestry of Homo and its relation
to earlier australopithecines remain unresolved. Here we report
on two partial skeletons with an
age of 1.95 to 1.78 million years. The fossils were encased in
cave deposits at the Malapa site in
South Africa. The skeletons were found close together and are
directly associated with craniodental
remains. Together they represent a new species of
Australopithecus that is probably descended
from Australopithecus africanus. Combined craniodental and
postcranial evidence demonstrates
that this new species shares more derived features with early
Homo than any other australopith
species and thus might help reveal the ancestor of that genus.
T
he origin of the genus Homo is widely
debated, with several candidate ancestors
being proposed in the genus Australopith-
ecus (1–3) or perhaps Kenyanthropus (4). The
earliest occurrence of fossils attributed to Homo
(H. aff. H. habilis) at 2.33 million years ago (Ma)
in Ethiopia (5) makes it temporally antecedent to
all other known species of the genus Homo.
Within early Homo, the hypodigms and phylo-
genetic relationships between H. habilis and
another early species, H. rudolfensis, remain
unresolved (6–8), and the placement of these
species within Homo has been challenged (9).
H. habilis is generally thought to be the ancestor
of H. erectus (10–13), although this might be
questioned on the basis of the considerable
temporal overlap that existed between them
(14). The identity of the direct ancestor of the

genus Homo, and thus its link to earlier Australo-
pithecus, remains controversial. Here we describe
two recently discovered, directly associated, par-
tially articulated Australopithecus skeletons from
the Malapa site in South Africa, which allow us
to investigate several competing hypotheses re-
garding the ancestry of Homo. These skeletons
cannot be accommodated within any existing
fossil taxon; thus, we establish a new species,
Australopithecus sediba, on the basis of a com-
bination of primitive and derived characters of the
cranium and postcranium.
The following is a description of Au. sediba:
Order Primates Linnaeus 1758; suborder Anthro-
poidea Mivart 1864; superfamily Hominoidea
Gray 1825; family Hominidae Gray 1825; genus
Australopithecus DART 1925; species Australo-
pithecus sediba sp. nov.
Etymology. The word sediba means “foun-
tain” or “wellspring” in the seSotho language.
Holotype and paratype. Malapa Hominin
1 (MH1) is a juvenile individual represented by
a partial cranium, fragmented mandible, and par-
tial postcranial skeleton that we designate as
the species holotype [Figs. 1 and 2, supporting
online material (SOM) text S1, figs. S1 and S2,
and table S1]. The first hominin specimen re-
covered from Malapa was the right clavicle of
MH1 (UW88-1), discovered by Matthew Berger
on 15 August 2008. MH2 is an adult individual
represented by isolated maxillary teeth, a partial
mandible, and partial postcranial skeleton that we

designate as the species paratype. Although MH1
is a juvenile, the second molars are already
erupted and in occlusion. Using either a human
or an ape model, this indicates that MH1 had
probably attained at least 95% of adult brain size
(15). Although additional growth would have
occurred in the skull and skeleton of this
individual, we judge that it would not have
appreciably altered the morphology on which
this diagnosis is based.
Locality. The two Au. sediba type skeletons
were recovered from the Malapa site (meaning
“homestead” in seSotho), situated roughly 15 km
NNE of the well-known sites of Sterkfontein,
Swartkrans, and Kromdraai in Gauteng Province,
South Africa. Detailed information regarding
geology and dating of the site is in (16).
RESEARCH ARTICLES
1Institute for Human Evolution, University of the
Witwatersrand,
Private Bag 3, Wits 2050, South Africa. 2School of
Geosciences,
University of the Witwatersrand, Private Bag 3, Wits 2050,
South
Africa. 3Department of Anthropology, Texas A&M University,
College Station, TX 77843, USA. 4Department of Evolutionary
Anthropology, Box 90383, Duke University, Durham, NC
27708,
USA. 5Anthropological Institute and Museum, University of
Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
6Department of Anthropology, Indiana University,
Bloomington,
IN 47405, USA. 7School of Earth and Environmental Sciences,

James Cook University, Townsville, Queensland 4811,
Australia.
*To whom correspondence should be addressed. E-mail:
[email protected]
Fig. 1. Craniodental elements of Au. sediba. UW88-50 (MH1)
juvenile cranium in (A) superior, (B)
frontal, and (C) left lateral views. (D) UW88-8 (MH1) juvenile
mandible in right lateral view, (E)
UW88-54 (MH2) adult mandible in right lateral view, (F)
UW88-8 mandible in occlusal view, (G)
UW 88-54 mandible in occlusal view, and (H) UW 88-50 right
maxilla in occlusal view (scale bars
are in centimeters).
www.sciencemag.org SCIENCE VOL 328 9 APRIL 2010 195
CORRECTED 17 DECEMBER 2010; SEE LAST PAGE
Diagnosis. Au. sediba can be distinguished
from other species of Australopithecus by a
combination of characters presented in Table 1;
comparative cranial measures are presented in
Table 2. A number of derived characters separate
Au. sediba from the older chronospecies Au.
anamensis and Au. afarensis. Au. sediba exhibits
neither the extreme megadontia, extensive cra-
nial cresting, nor facial prognathism of Au. garhi.
The suite of derived features characterizing
Au. aethiopicus, Au. boisei, and Au. robustus,
in particular the pronounced cranial muscle mark-
ings, derived facial morphology, mandibular
corpus robusticity, and postcanine megadontia,
are absent in Au. sediba. The closest morpholog-

ical comparison for Au. sediba is Au. africanus,
as these taxa share numerous similarities in the
cranial vault, facial skeleton, mandible, and
teeth (Table 1). Nevertheless, Au. sediba can be
readily differentiated from Au. africanus on
both craniodental and postcranial evidence.
Among the more notable differences, we ob-
serve that although the cranium is small, the
vault is relatively transversely expanded with
vertically oriented parietal walls and widely
spaced temporal lines; the face lacks the pro-
nounced, flaring zygomatics of Au. africanus;
the arrangement of the supraorbital torus, naso-
alveolar region, infraorbital region, and zy-
gomatics result in a derived facial mask; the
mandibular symphysis is vertically oriented with
a slight bony chin and a weak post-incisive pla-
num; and the teeth are differentiated by the
weakly defined buccal grooves of the maxillary
premolars, the weakly developed median lingual
ridge of the mandibular canine, and the small
absolute size of the postcanine dentition. These
exact differences also align Au. sediba with the
genus Homo (see SOM text S2 for hypodigms used
in this study). However, we consider Au. sediba
to be more appropriately positioned within
Australopithecus, based on the following cranio-
dental features: small cranial capacity, pronounced
glabelar region, patent premaxillary suture,
moderate canine jugum with canine fossa, small
anterior nasal spine, steeply inclined zygomati-
coalveolar crest, high masseter origin, moderate
development of the mesial marginal ridge of the
maxillary central incisor, and relatively closely
spaced premolar and molar cusps.

Postcranially, Au. sediba is similar to other
australopiths in its small body size, its relatively
long upper limbs with large joint surfaces, and
the retention of apparently primitive charac-
teristics in the upper and lower limbs (table S2).
Au. sediba differs from other australopiths, but
shares with Homo a number of derived features
of the os coxa, including increased buttressing of
the ilium and expansion of its posterior portion,
relative reduction in the distance between the
sacroiliac and hip joints, and reduction of dis-
tance from the acetabulum to the ischial tuberos-
ity. These synapomorphies with Homo anticipate
the reorganization of the pelvis and lower limb in
H. erectus and possibly the emergence of more
energetically efficient walking and running in
that taxon (17). As with the associated cranial
remains, the postcranium of Au. sediba is defined
not by the presence of autapomorphic features
but by a unique combination of primitive and
derived traits.
Cranium. The cranium is fragmented and
slightly distorted. The minimum cranial capacity
of MH1 is estimated at 420 cm3 (SOM text S4).
The vault is ovoid, with transversely expanded,
vertically oriented parietal walls. The widely
spaced temporal lines do not approach the
midline. Postorbital constriction is slight. The
weakly arched supraorbital torus is moderately
developed and laterally extended, with sharply
angled lateral corners and a weakly defined
supratoral sulcus. A robust glabelar region is
evident, with only a faint depression of the

supraorbital torus at the midline. The frontal
process of the zygomatic faces primarily laterally
and is expanded medially but not laterally. The
zygomatic prominence does not show antero-
lateral expansion. The zygomatics are weakly
flared laterally, resulting in an uninterrupted
frontal profile of the facial mask that is squared
superiorly and tapered inferiorly. The zygomat-
icoalveolar crests are long, straight, and steep-
ly inclined, resulting in a high masseter origin.
The root of the zygomatic begins at the anterior
margin of M1. The nasal bones are widened
superiorly, become narrowest about one-third
of the way down, and flare to their widest extent
at their inferior margin. The nasal bones are
elevated as a prominent ridge at the internasal
suture, with an increasingly anterior projection
inferiorly. The bone surface of the maxilla re-
treats gently away from the nasal aperture lat-
erally, resulting in an everted margin of the
superolateral portion of the aperture relative to
the infraorbital region. The inferolateral portion
of the nasal aperture becomes bluntly rounded.
The infraorbital region is slightly convex (18)
and is oriented at an approximately right angle
to the alveolar plane. There is a trace of a pre-
maxillary suture near the superolateral margin
of the nasal aperture. Prominent canine juga
delineate moderately developed canine fossae.
Anterior pillars are absent. The inferior margin
of the nasal aperture is marked by a stepped
nasal sill and a small but distinct anterior nasal
spine. The subnasal region is straight in the cor-
onal plane and only weakly projecting relative
Fig. 2. Associated skeletal elements of MH1 (left) and MH2

(right), in approximate anatomical position,
superimposed over an illustration of an idealized Au. africanus
skeleton (with some adjustment for
differences in body proportions). The proximal right tibia of
MH1 has been reconstructed from a natural
cast of the proximal metaphysis.
9 APRIL 2010 VOL 328 SCIENCE www.sciencemag.org196
RESEARCH ARTICLES
co
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w
Lo
w
Lo
w
H
ig
h
H
ig

h
H
ig
h
Fr
on
ta
l
tr
ig
on
Pr
es
en
t
Pr
es
en
t
A
bs
en
t
A
bs
en
t
A
bs

en
t
A
bs
en
t
A
bs
en
t
Pr
es
en
t
Pr
es
en
t
Pr
es
en
t
Su
pr
ag
le
no
id
gu

tt
er
w
id
th
N
ar
ro
w
?
N
ar
ro
w
N
ar
ro
w
N
ar
ro
w
N
ar
ro
w
N
ar
ro

w
W
id
e
W
id
e
W
id
e
H
or
iz
on
ta
l
di
st
an
ce
be
tw
ee
n
TM
J
an
d
M

2/
M
3
(6
)
Lo
ng
?
Lo
ng
Sh
or
t
Sh
or
t
Lo
ng
Sh
or
t
Lo
ng
Lo
ng
Lo
ng

Pa
ri
et
al
tr
an
sv
er
se
ex
pa
ns
io
n/
tu
be
r
A
bs
en
t
A
bs
en
t
A
bs
en
t

Pr
es
en
t
Pr
es
en
t
Pr
es
en
t
Pr
es
en
t
A
bs
en
t
A
bs
en
t
A
bs
en
t
Fa

ci
al
sk
el
et
o
n
Su
pr
ao
rb
it
al
ex
pr
es
si
on
Co
st
a
su
pr
.
Co
st
a
su
pr
.

In
te
rm
ed
.
To
ru
s
To
ru
s
In
te
rm
ed
.
To
ru
s
Co
st
a
su
pr
.
Co
st
a

su
pr
.
Co
st
a
su
pr
.
Su
pr
ao
rb
it
al
co
nt
ou
r
Le
ss
ar
ch
ed
Le
ss
ar
ch
ed

V
ar
ia
bl
e
A
rc
he
d
A
rc
he
d
A
rc
he
d
A
rc
he
d
Le
ss
ar
ch
ed
V
ar

ia
bl
e
A
rc
he
d
G
la
be
lla
r
re
gi
on
fo
rm
s
as
pr
om
in
en
t
bl
oc
k
N
o

N
o
V
ar
ia
bl
e
Ye
s
N
o
V
ar
ia
bl
e
N
o
N
o
Ye
s
Ye
s
La
t.

ha
lf
of
in
fr
ao
rb
it
al
m
ar
gi
n
bl
un
t
an
d
pr
ot
ru
di
ng
N
o
?
N
o
N
o

N
o
N
o
N
o
Ye
s
N
o
Ye
s
Zy
go
m
at
ic
ar
ch
re
la
ti
ve
to
in
fe
ri

or
or
bi
ta
l
m
ar
gi
n
A
bo
ve
?
Le
ve
l
Le
ve
l
Le
ve
l
?
Le
ve
l
A
bo
ve

A
bo
ve
A
bo
ve
Co
nv
ex
it
y/
co
nc
av
it
y
of
in
fr
ao
rb
it
al
re
gi
on
?
?
Co

nv
ex
Co
nv
ex
Co
nc
av
e
Co
nc
av
e
Co
nv
ex
Co
nc
av
e
Co
nc
av
e
Co
nc
av
e

N
as
al
bo
ne
pr
oj
ec
ti
on
ab
ov
e
fr
on
to
m
ax
ill
ar
y
su
tu
re
Ex
pa
nd
ed
?
V

ar
ia
bl
e
N
o
N
o
N
o
N
o
Ta
pe
re
d
Ex
pa
nd
ed
Ex
pa
nd
ed
In
fe
ri
or

w
id
th
of
pr
oj
ec
ti
ng
na
sa
l
bo
ne
(2
5)
W
id
e
?
V
ar
ia
bl
e
W
id
e

V
ar
ia
bl
e
N
ar
ro
w
W
id
e
N
ot
pr
oj
.
N
ot
pr
oj
.
N
ot
pr
oj
.

In
fr
ao
rb
it
al
fo
ra
m
en
he
ig
ht
(3
2)
H
ig
h
?
V
ar
ia
bl
e
H
ig
h
H
ig

h
?
H
ig
h
Lo
w
Lo
w
Lo
w
RESEARCH ARTICLES
C
h
ar
ac
te
rs
A
u.
af
ar
en
si

s
A
u.
ga
rh
i
A
u.
af
ri
ca
nu
s
A
u.
se
di
ba
H
.
ha
bi
li
s
H
.

ru
do
lf
en
si
s
H
.
er
ec
tu
s
A
u.
ae
th
io
pi
cu
s
A
u.
bo
is
ei
A
u.

ro
bu
st
us
Ca
ni
ne
ju
ga
pr
om
in
en
ce
/a
nt
er
io
r
pi
lla
rs
Pr
om
in
en
t

Pr
om
in
en
t
V
ar
ia
bl
e
Pr
om
in
en
t
V
ar
ia
bl
e
W
ea
k
W
ea
k
W
ea

k
W
ea
k
Pi
lla
rs
Pa
te
nc
y
of
pr
em
ax
ill
ar
y
su
tu
re
O
bl
it
er
at
ed
?

O
cc
as
io
na
l
Tr
ac
e
O
bl
it
er
at
ed
O
bl
it
er
at
ed
O
bl
it
er
at
ed
O
bl
it
er

at
ed
O
bl
it
er
at
ed
O
cc
as
io
na
l
In
fe
ro
la
te
ra
l
na
sa
l
ap
er
tu
re
m
ar
gi

n
Sh
ar
p
Sh
ar
p
V
ar
ia
bl
e
B
lu
nt
V
ar
ia
bl
e
Sh
ar
p
B
lu
nt
B
lu

nt
V
ar
ia
bl
e
B
lu
nt
Ev
er
si
on
of
su
pe
ri
or
na
sa
l
ap
er
tu
re
m
ar
gi
n

?
?
N
on
e
Sl
ig
ht
Sl
ig
ht
Sl
ig
ht
Sl
ig
ht
Sl
ig
ht
V
ar
ia
bl
e
N
on

e
N
as
oa
lv
eo
la
r
tr
ia
ng
ul
ar
fr
am
e/
gu
tt
er
Tr
ia
ng
ul
ar
?
Tr
ia
ng
ul
ar

Tr
ia
ng
ul
ar
Tr
ia
ng
ul
ar
Tr
ia
ng
ul
ar
Tr
ia
ng
ul
ar
G
ut
te
r
G
ut
te
r
G
ut

te
r
N
as
al
ca
vi
ty
en
tr
an
ce
St
ep
pe
d
St
ep
pe
d
St
ep
pe
d
St
ep
pe
d

V
ar
ia
bl
e
St
ep
pe
d
St
ep
pe
d
Sm
oo
th
Sm
oo
th
Sm
oo
th
N
as
oa
lv
eo
la
r
cl

iv
us
co
nt
ou
r
in
co
ro
na
l
pl
an
e
Co
nv
ex
Co
nv
ex
St
ra
ig
ht
St
ra
ig
ht
St

ra
ig
ht
St
ra
ig
ht
St
ra
ig
ht
Co
nc
av
e
Co
nc
av
e
Co
nc
av
e
Su
bn
as
al
pr
oj

ec
ti
on
(3
8)
M
ar
ke
d
M
ar
ke
d
V
ar
ia
bl
e
W
ea
k
V
ar
ia
bl
e
W
ea
k

W
ea
k
M
ar
ke
d
M
od
er
at
e
M
od
er
at
e
Ca
ni
ne
fo
ss
a
Pr
es
en
t
Pr

es
en
t
Pr
es
en
t
Pr
es
en
t
Pr
es
en
t
A
bs
en
t
A
bs
en
t
A
bs
en
t
A
bs

en
t
A
bs
en
t
M
ax
ill
ar
y
fo
ss
ul
a
A
bs
en
t
A
bs
en
t
A
bs
en
t
A
bs
en

t
A
bs
en
t
A
bs
en
t
A
bs
en
t
A
bs
en
t
A
bs
en
t
Pr
es
en
t
In
ci
so
r

pr
oc
um
be
nc
y
Pr
oc
um
b.
Pr
oc
um
b.
V
ar
ia
bl
e
V
er
ti
ca
l
V
ar
ia
bl
e

V
er
ti
ca
l
V
er
ti
ca
l
V
er
ti
ca
l
V
er
ti
ca
l
V
er
ti
ca
l
A
nt
er
io
r
na

sa
l
sp
in
e
re
l.
to
na
sa
l
ap
er
tu
re
A
bs
en
t
?
A
nt
er
io
r
A
nt
er
io
r
A

nt
er
io
r
?
En
la
rg
ed
Po
st
er
io
r
Po
st
er
io
r
Po
st
er
io
r
Ex
pa
ns
io
n
of

fr
on
ta
l
pr
oc
es
s
of
zy
go
m
at
ic
bo
ne
M
ed
.
an
d
la
t.
?
M
ed
.
an
d
la
t.

M
ed
ia
l
M
ed
ia
l
M
ed
ia
l
M
ed
ia
l
M
ed
.
an
d
la
t.
M
ed
.
an
d
la
t.

M
ed
.
an
d
la
t.
A
ng
ul
ar
in
de
nt
at
io
n
of
la
te
ra
l
or
bi
ta
l
m
ar
gi
n
?
?

In
de
nt
ed
Cu
rv
ed
Cu
rv
ed
Cu
rv
ed
Cu
rv
ed
?
Cu
rv
ed
Cu
rv
ed
Zy
go
m
at
ic

pr
om
in
en
ce
de
ve
lo
pm
en
t
Pr
om
in
en
t
?
Pr
om
in
en
t
Sl
ig
ht
Sl
ig

ht
?
Sl
ig
ht
Pr
om
in
en
t
Pr
om
in
en
t
Pr
om
in
en
t
La
te
ra
l
fl
ar
in
g

of
zy
go
m
at
ic
ar
ch
es
M
ar
ke
d
?
M
ar
ke
d
Sl
ig
ht
Sl
ig
ht
Sl
ig
ht
Sl
ig

ht
M
ar
ke
d
M
ar
ke
d
M
ar
ke
d
O
ut
lin
e
of
su
pe
ri
or
fa
ci
al
m
as
k

Ta
pe
re
d
?
Ta
pe
re
d
Sq
ua
re
d
Sq
ua
re
d
Sq
ua
re
d
Sq
ua
re
d
Ta
pe
re
d

Ta
pe
re
d
Ta
pe
re
d
Zy
go
m
at
ic
oa
lv
eo
la
r
cr
es
t/
m
al
ar
no
tc
h
St
ra
ig

ht
?
St
ra
ig
ht
St
ra
ig
ht
N
ot
ch
N
ot
ch
N
ot
ch
St
ra
ig
ht
St
ra
ig
ht
St

ra
ig
ht
In
fr
ao
rb
it
al
pl
at
e
an
gl
e
re
la
ti
ve
to
al
ve
ol
ar
pl
an
e
O
bt
us

e
?
O
bt
us
e
R
ig
ht
R
ig
ht
R
ig
ht
R
ig
ht
O
bt
us
e
O
bt
us
e
O
bt

us
e
Zy
go
m
at
ic
om
ax
ill
ar
y
st
ep
s
an
d
fo
ss
ae
pr
es
en
t
N
o
?
N
o

N
o
N
o
N
o
N
o
N
o
N
o
Ye
s
H
ei
gh
t
of
m
as
se
te
r
or
ig
in

(3
5)
Lo
w
Lo
w
H
ig
h
H
ig
h
Lo
w
Lo
w
Lo
w
H
ig
h
H
ig
h
H

ig
h
M
al
ar
th
ic
kn
es
s
(3
1)
Th
in
?
Th
in
Th
in
Th
in
?
Th
in
Th
ic
k

Th
ic
k
Th
ic
k
Pr
oj
ec
ti
on
of
zy
go
m
at
ic
s
re
la
ti
ve
to
na
sa
l
bo
ne
s
Po

st
er
io
r
Po
st
er
io
r
V
ar
ia
bl
e
Po
st
er
io
r
Po
st
er
io
r
Le
ve
l
Po
st
er

io
r
A
nt
er
io
r
A
nt
er
io
r
A
nt
er
io
r
Fa
ci
al
pr
og
na
th
is
m
(7
)
(s

el
lio
n-
pr
os
th
io
n
an
gl
e)
Pr
og
na
th
ic
Pr
og
na
th
ic
V
ar
ia
bl
e
M
es
og
na
th
.

M
es
og
na
th
.
M
es
og
na
th
.
O
rt
ho
gn
.
Pr
og
na
th
ic
M
es
og
na
th
.
M
es

og
na
th
.
M
as
se
te
ri
c
po
si
ti
on
re
la
ti
ve
to
se
lli
on
A
nt
er
io
r
?
Po
st
er

io
r
Po
st
er
io
r
Po
st
er
io
r
?
Po
st
er
io
r
A
nt
er
io
r
A
nt
er
io
r
A
nt

er
io
r
La
te
ra
l
an
te
ri
or
fa
ci
al
co
nt
ou
r
B
ip
ar
ti
te
B
ip
ar
ti
te
V
ar

ia
bl
e
St
ra
ig
ht
V
ar
ia
bl
e
St
ra
ig
ht
St
ra
ig
ht
St
ra
ig
ht
St
ra
ig
ht
St

ra
ig
ht
RESEARCH ARTICLES
C
h
ar
ac
te
rs
A
u.
af
ar
en
si
s
A
u.
ga
rh
i
A
u.

af
ri
ca
nu
s
A
u.
se
di
ba
H
.
ha
bi
li
s
H
.
ru
do
lf
en
si
s
H
.
er

ec
tu
s
A
u.
ae
th
io
pi
cu
s
A
u.
bo
is
ei
A
u.
ro
bu
st
us
P
al
at
e
Pr

ot
ru
st
io
n
of
in
ci
so
rs
be
yo
nd
bi
-c
an
in
e
lin
e
Ye
s
Ye
s
Ye
s
Ye
s

Ye
s
N
o
Ye
s
N
o
N
o
N
o
A
nt
er
io
r
pa
la
ta
l
de
pt
h
Sh
al
lo
w

Sh
al
lo
w
D
ee
p
D
ee
p
V
ar
ia
bl
e
D
ee
p
V
ar
ia
bl
e
Sh
al
lo
w
D
ee

p
Sh
al
lo
w
D
en
ta
l
ar
ca
de
sh
ap
e
R
ec
ta
ng
le
R
ec
ta
ng
le
V
ar
ia
bl
e

Pa
ra
bo
lic
Pa
ra
bo
lic
Pa
ra
bo
lic
Pa
ra
bo
lic
R
ec
ta
ng
le
Pa
ra
bo
lic
Pa
ra
bo
lic

M
ax
ill
ar
y
I2
/C
di
as
te
m
a
Pr
es
en
t
Pr
es
en
t
A
bs
en
t
A
bs
en
t
V

ar
ia
bl
e
A
bs
en
t
A
bs
en
t
A
bs
en
t
A
bs
en
t
A
bs
en
t
M
an
d
ib
le

O
ri
en
ta
ti
on
of
m
an
di
bu
la
r
sy
m
ph
ys
is
R
ec
ed
in
g
?
R
ec
ed
in
g
V

er
ti
ca
l
V
er
ti
ca
l
V
er
ti
ca
l
V
er
ti
ca
l
V
er
ti
ca
l
V
er
ti
ca
l
V

er
ti
ca
l
B
on
y
ch
in
(m
en
tu
m
os
se
um
)
A
bs
en
t
?
Sl
ig
ht
Sl
ig
ht
Sl

ig
ht
Sl
ig
ht
Sl
ig
ht
Sl
ig
ht
Sl
ig
ht
Sl
ig
ht
D
ir
ec
ti
on
of
m
en
ta
l
fo

ra
m
en
op
en
in
g
V
ar
ia
bl
e
?
V
ar
ia
bl
e
La
te
ra
l
La
te
ra
l
La
te
ra
l

La
te
ra
l
La
te
ra
l
La
te
ra
l
La
te
ra
l
Po
st
-i
nc
is
iv
e
pl
an
um
Pr
om
in

en
t
?
Pr
om
in
en
t
W
ea
k
Pr
om
in
en
t
W
ea
k
W
ea
k
Pr
om
in
en
t

Pr
om
in
en
t
Pr
om
in
en
t
To
ru
s
m
ar
gi
na
lis
an
d
m
ar
gi
na
l
tu
be
rc
le

s
Pr
om
in
en
t
?
M
od
er
at
e
M
od
er
at
e
M
od
er
at
e
Pr
om
in
en
t
Pr

om
in
en
t
?
Pr
om
in
en
t
Pr
om
in
en
t
M
an
di
bu
la
r
co
rp
us
cr
os
s-
se
ct

io
na
l
ar
ea
at
M
1
(5
0)
Sm
al
l
?
Sm
al
l
Sm
al
l
Sm
al
l
V
ar
ia
bl
e

Sm
al
l
La
rg
e
La
rg
e
La
rg
e
Te
et
h
In
ci
so
r-
to
-p
os
tc
an
in
e
ra
ti
o
(m

ax
ill
ar
y)
(6
0)
La
rg
e
M
od
er
at
e
M
od
er
at
e
M
od
er
at
e
M
od
er
at
e

M
od
er
at
e
La
rg
e
?
Sm
al
l
Sm
al
l
Ca
ni
ne
-t
o-
po
st
ca
ni
ne
ra
ti
o
(m

ax
ill
ar
y/
m
an
di
bu
la
r)
(6
1,
62
)
La
rg
e
La
rg
e
La
rg
e
La
rg
e
La
rg
e

La
rg
e
La
rg
e
?
Sm
al
l
Sm
al
l
Po
st
ca
ni
ne
cr
ow
n
ar
ea
(m
ax
ill
ar
y/

m
an
di
bu
la
r)
(5
7,
59
)
M
od
er
at
e
La
rg
e
La
rg
e
M
od
er
at
e
M
od
er
at

e
La
rg
e
Sm
al
l
La
rg
e
La
rg
e
La
rg
e
M
ax
ill
ar
y
I1
:
M
M
R
de
ve
lo

pm
en
t,
lin
gu
al
fa
ce
M
od
er
at
e
?
M
od
er
at
e
M
od
er
at
e
W
ea
k
W

ea
k
W
ea
k
?
M
od
er
at
e
M
od
er
at
e
M
ax
ill
ar
y
C:
de
ve
lo
pm
en
t
of

lin
gu
al
ri
dg
es
M
ar
ke
d
M
ar
ke
d
M
ar
ke
d
W
ea
k
W
ea
k
M
ar
ke
d

M
ar
ke
d
?
M
ar
ke
d
W
ea
k
M
ax
ill
ar
y
pr
em
ol
ar
m
ol
ar
iz
at
io
n
N

on
e
M
in
or
M
in
or
N
on
e
M
in
or
M
in
or
N
on
e
M
ar
ke
d
M
ar
ke
d

M
ar
ke
d
M
ax
ill
ar
y
pr
em
ol
ar
s:
bu
cc
al
gr
oo
ve
s
M
ar
ke
d
M
ar
ke
d

M
ar
ke
d
W
ea
k
W
ea
k
M
ar
ke
d
W
ea
k
?
W
ea
k
W
ea
k
M
ed
ia
n

lin
gu
al
ri
dg
e
of
m
an
di
bu
la
r
ca
ni
ne
Pr
om
.
?
Pr
om
.
W
ea
k
W
ea

k
W
ea
k
W
ea
k
?
W
ea
k
W
ea
k
M
an
di
bu
la
r
P 3
ro
ot
nu
m
be
r
2

?
2
2
1
2
1
?
2
2
Pr
ot
oc
on
id
/m
et
ac
on
id
m
or
e
m
es
ia
l
cu
sp
(m

ol
ar
s)
Eq
ua
l
?
Eq
ua
l
Pr
ot
oc
on
id
Pr
ot
oc
on
id
Pr
ot
oc
on
id
Pr
ot
oc
on
id

?
Eq
ua
l
Eq
ua
l
Pe
ak
of
en
am
el
fo
rm
s
be
tw
ee
n
ro
ot
s
of
m
ol
ar
s

N
o
?
Ye
s
Ye
s
N
o
N
o
N
o
?
N
o
Ye
s
R
el
at
iv
e
en
am
el
th

ic
kn
es
s
Th
ic
k
Th
ic
k
Th
ic
k
Th
ic
k
Th
ic
k
Th
ic
k
Th
ic
k
H
yp
er

H
yp
er
H
yp
er
Po
si
ti
on
s
of
ap
ic
es
of
lin
gu
al
(L
C)
an
d
bu
cc
al
(B

C)
cu
sp
s
of
pr
em
ol
ar
s
an
d
m
ol
ar
s
re
la
ti
ve
to
oc
cl
us
al
m
ar
gi
n

LC
at
m
ar
gi
n,
B
C
sl
ig
ht
ly
lin
gu
al
LC
at
m
ar
gi
n,
B
C
sl
ig
ht
ly

lin
gu
al
LC
sl
ig
ht
ly
bu
cc
al
,
B
C
m
od
er
at
el
y
lin
gu
al
LC
sl
ig
ht
ly
bu
cc

al
,
B
C
m
od
er
at
el
y
lin
gu
al
LC
at
m
ar
gi
n,
B
C
sl
ig
ht
ly
lin
gu
al

lin
gu
al
LC
m
od
.
bu
cc
al
,
B
C
st
ro
ng
ly
lin
gu
al
LC
m
od
.
bu
cc
al
,
B
C

st
ro
ng
ly
lin
gu
al
LC
m
od
.
bu
cc
al
,
B
C
st
ro
ng
ly
lin
gu
al
RESEARCH ARTICLES

co
nt
in
ue
d
on
ne
xt
pa
ge
Ta
b
le
2
.
Cr
an
io
de
nt
al
m
ea
su
re
m
en
ts
fo
r

ea
rl
y
ho
m
in
in
s
in
Af
ri
ca
.
Au
.
se
di
ba
is
re
pr
es
en
te
d
by
M
H
1.
U
nl
es

s
ot
he
rw
is
e
de
fi
ne
d,
m
ea
su
re
m
en
ts
ar
e
ba
se
d
on
(6
).
So
m
e
m

ea
su
re
s
w
er
e
un
av
ai
la
bl
e
fo
r
sp
ec
im
en
s
of
Au
.
af
ar
en
si
s
an
d
Au
.
ga
rh

i,
in
w
hi
ch
ca
se
th
e
ch
ar
ac
te
r
st
at
es
in
Ta
bl
e
1
w
er
e
es
ti
m
at
ed
.
Se

ve
ra
l
ch
ar
ac
te
r
st
at
es
in
Ta
bl
e
1
ar
e
re
co
rd
ed
as
va
ri
ab
le
,
al
th
ou
gh
on

ly
sp
ec
ie
s
av
er
ag
e
va
lu
es
ar
e
pr
es
en
te
d
he
re
.
M
ea
su
re
m
en
ts
ar
e
in

m
ill
im
et
er
s
un
le
ss
ot
he
rw
is
e
in
di
ca
te
d.
D
es
cr
ip
ti
on
s
of
ch
ar
ac
te
r

st
at
es
pr
es
en
te
d
in
Ta
bl
e
1
th
at
ar
e
ba
se
d
on
m
ea
su
re
m
en
ts
fr
om

th
is
ta
bl
e
ar
e
pr
ov
id
ed
in
SO
M
te
xt
S3
.
A
bb
re
vi
at
io
ns
ar
e
as
fo
llo
w

s:
br
,
br
eg
m
a;
ek
,
ec
to
co
nc
hi
on
;
ek
m
,
ec
to
m
ol
ar
e;
fm
t,
fr
on
to
m
ol
ar
e

te
m
po
ra
le
;
ft
,
fr
on
to
te
m
po
ra
le
;
g,
gl
ab
el
la
;
m
f,
m
ax
ill
of
ro
nt
al
e;

n,
na
si
on
;
ns
,
na
so
sp
in
al
e;
or
,
or
bi
ta
le
;
po
,
po
ri
on
;
pr
,
pr
os
th
io
n;

rh
i,
rh
in
io
n;
zm
,
zy
go
m
ax
ill
ar
e;
zy
,
zy
gi
on
;
zy
o,
zy
go
or
bi
ta
le
.
Ite
m

Me
as
ur
em
en
t
de
sc
rip
tio
n
in
(6
)
Me
as
ur
em
en
t
Au
.
af
ar
en
sis

Au
.
af
ric
an
us
Au
.
se
dib
a
H.
ha
bil
is
H.
ru
do
lfe
ns
is
H.
er
ec
tu
s

Au
.
ae
th
iop
icu
s
Au
.
bo
ise
i
Au
.
ro
bu
stu
s
1
Cr
an
ia
l
ca
pa
ci
ty

(c
m
3
)
41
5
44
2
42
0
63
1
75
1
90
0
41
9
51
5
53
0
2
9
M

ax
im
um
pa
ri
et
al
br
ea
dt
h
90
99
10
0
10
3
11
4
12
6
94
99
10
0
3

11
B
i-
po
ri
on
ic
br
ea
dt
h
(p
o-
po
)
12
6
99
10
4
10
4
12
7
12
1
12
5

11
6
—
4
Po
st
or
bi
ta
l
co
ns
tr
ic
ti
on
(n
ar
ro
w
es
t
po
in
t
be
hi
nd
th
e
or
bi

ts
)
77
69
73
76
85
89
65
64
73
5
Po
st
or
bi
ta
l
co
ns
tr
ic
ti
on
in
de
x
(4
/1

4
×
10
0)
66
71
85
70
72
80
65
61
68
6
H
or
iz
on
ta
l
di
st
an
ce
be
tw
ee
n
TM

J
an
d
M
2
/M
3
83
61
45
51
58
57
94
82
81
7
Fa
ci
al
pr
og
na
th
is
m
(s

el
lio
n-
pr
os
th
io
n
an
gl
e)
63
61
65
65
68
72
41
66
69
8
75
In
fr
at
em
po
ra
l

fo
ss
a
de
pt
h
–
31
21
27
–
37
51
50
36
9
8
M
in
im
um
fr
on
ta
l
br
ea
dt
h

(f
t-
ft
)
40
54
70
66
72
76
33
36
35
10
17
G
la
be
lla
to
br
eg
m
a
(g
-b
r)
10

1
80
75
83
86
10
3
–
87
–
11
Fr
on
ta
l
ch
or
d
(n
-b
r)
–
84
74
80
93
99

–
84
–
12
62
Su
pr
ao
rb
it
al
to
ru
s
ve
rt
ic
al
th
ic
kn
es
s
–
8
8
8
10

12
10
12
9
13
43
Su
pe
ri
or
fa
ci
al
he
ig
ht
(n
-p
r)
87
78
68
68
90
76
99

10
0
80
14
49
Su
pe
ri
or
fa
ci
al
br
ea
dt
h
(f
m
t-
fm
t)
11
7
97
86
10
0

11
7
10
7
10
0
10
8
10
7
15
50
B
i-
or
bi
ta
l
br
ea
dt
h
(e
k-
ek
)
89
84

78
89
10
0
99
10
1
93
82
16
52
B
iz
yg
om
at
ic
br
ea
dt
h
(z
y-
zy
)
15
7
12

6
10
2
11
7
–
13
5
15
3
16
5
14
3
17
Zy
go
m
at
ic
br
ea
dt
h
in
de
x
(1

4/
16
×
10
0)
75
74
84
85
–
84
–
65
74
18
53
B
im
ax
ill
ar
y
br
ea
dt
h
(z
m

-z
m
)
–
10
3
84
97
11
3
10
5
12
6
11
9
10
6
19
55
In
te
ro
rb
it
al

br
ea
dt
h
(m
f-
m
f)
18
19
20
27
24
25
23
24
24
20
56
O
rb
it
al
br
ea
dt
h
(m

f-
ek
)
38
36
31
33
39
39
36
37
33
21
57
O
rb
it
al
he
ig
ht
(p
er
pe
nd
ic
ul

ar
to
20
)
34
32
31
31
33
36
41
33
30
22
71
N
as
al
br
id
ge
le
ng
th
(n

-r
hi
)
–
27
26
18
20
18
35
30
28
23
73
N
as
al
br
id
ge
br
ea
dt
h
su
pe
ri
or

–
5
8
8
8
13
12
14
11
24
N
as
al
br
id
ge
br
ea
dt
h
at
an
te
ri
or
la

cr
im
al
cr
es
ts
–
11
5
10
–
24
19
11
–
25
74
N
as
al
br
id
ge
br
ea
dt
h

in
fe
ri
or
–
11
13
11
10
18
11
7
8
26
N
as
al
br
id
ge
he
ig
ht
(n
as
io
n

su
bt
en
se
at
an
te
ri
or
la
cr
im
al
cr
es
ts
)
–
4
9
8
–
9
4
5
–
27

69
N
as
al
he
ig
ht
(n
-n
s)
58
50
49
45
57
52
72
64
54
28
70
N
as
al
ap
er
tu

re
he
ig
ht
(r
hi
-n
s)
29
26
22
28
39
30
38
35
24
29
68
M
ax
im
um
na
sa
l
ap

er
tu
re
w
id
th
23
23
26
25
27
32
30
31
25
30
O
rb
it
oa
lv
eo
la
r
he
ig
ht
(o

r-
al
ve
ol
ar
pl
an
e)
55
53
44
47
59
51
53
69
57
31
60
M
al
ar
th
ic
kn
es
s

14
13
13
8
–
12
20
18
18
32
In
fr
ao
rb
it
al
fo
ra
m
en
he
ig
ht
(t
o
in
fe
ri

or
or
bi
ta
l
m
ar
gi
n)
–
12
15
15
14
16
30
25
26
33
Pr
os
th
io
n
to
zy
go
m

ax
ill
ar
e
(p
r-
zm
)
–
67
57
55
69
67
80
82
71
34
Pr
os
th
io
n
to
zy
go
or
bi
ta

le
(p
r-
zy
o)
–
60
50
57
75
70
73
81
69
35
M
as
se
te
r
or
ig
in
he
ig
ht
in

de
x
(3
3/
34
×
10
0)
–
11
2
10
4
96
92
96
11
0
10
1
10
3
36
47
Su
bn

as
al
e
to
pr
os
th
io
n
(h
or
iz
on
ta
l
pr
oj
ec
ti
on
)
28
23
13
19
17
16
23
27
26

37
48
Su
bn
as
al
to
pr
os
th
io
n
(v
er
ti
ca
l
pr
oj
ec
ti
on
)
15
21
17
18
30
21
12

25
22
38
Su
bn
as
al
e
pr
oj
ec
ti
on
in
de
x
(3
6/
37
×
10
0)
18
7
10
8
76
10

6
57
79
19
2
10
8
12
2
39
94
In
ci
so
r
al
ve
ol
ar
le
ng
th
–
13
16
15

14
16
15
15
13
40
96
Pr
em
ol
ar
al
ve
ol
ar
le
ng
th
–
15
18
16
16
13
21
22

17
RESEARCH ARTICLES
to the facial plane. The face is mesognathic.
The palate is consistently deep along its entire
extent, with a parabolic dental arcade.
Mandible. Descriptions apply to the more
complete juvenile (MH1) mandible unless other-
wise stated. The nearly vertical mandibular sym-
physis presents a weak lateral tubercle, resulting
in a slight mental trigone, and a weak man-
dibular incurvation results in a slight mentum
osseum. The post-incisive planum is weakly
developed and almost vertical. Both mandibular
corpora are relatively gracile, with a low height
along the alveolar margin. The extramolar sulcus
is relatively narrow in both mandibles. In MH1,
a moderate lateral prominence displays its
greatest protrusion at the mesial extent of M2,
with a marked decrease in robusticity to P4; in
MH2 the moderate lateral prominence shows
its greatest protrusion at M3, with a marked
decrease in robusticity to M2. The alveolar prom-
inence is moderately deep with a notable medial
projection posteriorly. The anterior and posterior
subalveolar fossae are continuous. The ramus
of MH1 is tall and narrow, with nearly parallel,
vertically oriented anterior and posterior bor-
ders; the ramus of MH2 is relatively broader,

with nonparallel anterior and posterior borders
(fig. S2). The mandibular notch is relatively deep
and narrow in MH1 and more open in MH2.
The coronoid extends farther superiorly than
the condyle. The condyle is mediolaterally broad
and anteroposteriorly narrow. The endocondyloid
buttress is absent in MH1, whereas in MH2 a
weak endocondyloid buttress approaches the
condyle without reaching it.
Dental size and proportions. The dentition
of the juvenile (MH1) is relatively small, whereas
preserved molars of the adult (MH2) are even
smaller (Fig. 3 and fig. S4). For MH1, the
maxillary central incisor is distinguishable only
from the reduced incisors of Au. robustus. The
maxillary canine is narrower than all canines of
Au. africanus except TM 1512, whereas the
mandibular canine falls well below the range of
Au. africanus. Premolars and molars are at the
lower end of the Au. africanus range and within
that of H. habilis–H. rudolfensis and H. erectus.
Molar dimensions of the adult individual (MH2)
are smaller than those of Au. africanus, are
at or below the range of those of H. habilis–
H. rudolfensis, and are within the range of those
of H. erectus. Au. sediba mirrors the Au. africanus
pattern of maxillary molars that increase slightly
in size posteriorly, though it differs in that the
molars tend to be considerably larger in the latter
taxon. Conversely, the Au. sediba pattern varies
slightly from that seen in specimens KNM-ER
1813, OH 13, and OH 65 and H. erectus, where-
in the molars increase from M1 to M2 but then
decrease to M3. In broad terms, the teeth of
Au. sediba are similar in size to teeth of speci-

mens assigned to Homo but share the closely
spaced cusp apices seen in Australopithecus.
Postcranium. Preserved postcranial remains
of Au. sediba (table S1) denote small-bodiedIte
m
Me
as
ur
em
en
t
de
sc
rip
tio
n
in
(6
)
Me
as
ur
em
en
t
Au

.
af
ar
en
sis
Au
.
af
ric
an
us
Au
.
se
dib
a
H.
ha
bil
is
H.
ru
do
lfe
ns
is

H.
er
ec
tu
s
Au
.
ae
th
iop
icu
s
Au
.
bo
ise
i
Au
.
ro
bu
stu
s
41
98

In
te
rc
an
in
e
di
st
an
ce
26
30
30
30
33
31
–
29
27
42
88
Pa
la
te
br
ea
dt
h
(e

km
-e
km
)
68
64
63
70
80
66
83
82
67
43
14
1
M
an
di
bu
la
r
sy
m
ph
ys
is
he

ig
ht
39
38
32
27
36
34
–
47
42
44
14
2
M
an
di
bu
la
r
sy
m
ph
ys
is
de
pt
h

60
20
19
19
24
19
–
28
25
45
14
7
M
an
di
bu
la
r
co
rp
us
he
ig
ht
at
P 4
34

33
28
30
38
30
–
42
38
46
14
8
M
an
di
bu
la
r
co
rp
us
de
pt
h
at
P 4
19
21

18
20
22
19
–
28
24
47
14
9
Cr
os
s-
se
ct
io
na
l
ar
ea
at
P 4
(c
al
cu
la
te
d
as

an
el
lip
se
)
51
1
55
8
38
2
42
7
65
3
45
8
–
91
0
70
9
48
15
0

M
an
di
bu
la
r
co
rp
us
he
ig
ht
at
M
1
33
32
28
29
36
30
35
41
37
49
15
1

M
an
di
bu
la
r
co
rp
us
de
pt
h
at
M
1
19
21
18
20
23
20
26
28
26
50
15
2

Cr
os
s-
se
ct
io
na
l
ar
ea
at
M
1
(c
al
cu
la
te
d
as
an
el
lip
se
)
48
8
53
2
39

6
42
1
66
7
46
9
71
5
91
3
75
9
51
15
4
M
an
di
bu
la
r
co
rp
us
he
ig

ht
at
M
2
31
31
25
31
36
30
–
41
35
52
15
5
M
an
di
bu
la
r
co
rp
us
de
pt

h
at
M
2
22
25
22
23
26
21
–
31
28
53
15
6
Cr
os
s-
se
ct
io
na
l
ar
ea
at

M
2
(c
al
cu
la
te
d
as
an
el
lip
se
)
53
6
61
2
43
6
53
7
74
5
50
4
–
98

0
77
0
54
16
2
H
ei
gh
t
of
m
en
ta
l
fo
ra
m
en
re
la
ti
ve
to
al
ve
ol
ar

m
ar
gi
n
20
19
13
13
17
13
–
20
20
55
M
ax
ill
ar
y
in
ci
so
r
cr
ow
n
ar
ea

(I
1
+
I2
)
14
3
13
5
10
9
13
2
13
7
13
6
–
11
7
10
9
56
M
ax
ill

ar
y
ca
ni
ne
cr
ow
n
ar
ea
10
7
10
4
79
95
11
8
96
–
76
79
57
M
ax
ill
ar

y
po
st
ca
ni
ne
cr
ow
n
ar
ea
71
3
86
8
73
1
75
5
82
9
61
7
–
10
12

94
1
58
M
an
di
bu
la
r
ca
ni
ne
cr
ow
n
ar
ea
87
95
68
83
–
79
–
72
61
59

M
an
di
bu
la
r
m
ol
ar
cr
ow
n
ar
ea
55
0
65
1
53
6
56
5
66
8
46
6

–
78
1
67
8
60
M
ax
ill
ar
y
in
ci
so
r
to
po
st
ca
ni
ne
ra
ti
o
20
.0
15
.6

14
.9
17
.4
16
.6
22
.1
–
11
.5
11
.6
61
M
ax
ill
ar
y
ca
ni
ne
to
po
st
ca
ni
ne

ra
ti
o
15
.0
11
.9
10
.8
12
.6
14
.2
15
.5
–
7.
5
8.
4
62
M
an
di
bu
la

r
ca
ni
ne
to
m
ol
ar
ra
ti
o
15
.8
14
.6
12
.7
14
.6
–
16
.7
–
9.
2
9.

0
RESEARCH ARTICLES
hominins that retain an australopith pattern of
long upper limbs, a high brachial index, and
relatively large upper limb joint surfaces
(table S2). In addition to these aspects of limb
and joint proportions, numerous other features
in the upper limb are shared with sibling species
of Australopithecus (to the exclusion of later
Homo), including a scapula with a cranially
oriented glenoid fossa and a strongly developed
axillary border; a prominent conoid tubercle on
the clavicle, with a pronounced angular margin;
low proximal-to-distal humeral articular propor-
tions; a distal humerus with a marked crest for
the brachioradialis muscle, a large and deep
olecranon fossa with a septal aperture, and a
marked trochlear/capitular keel (19); an ulna
with a pronounced flexor carpi ulnaris tubercle;
and long, robust, and curved manual phalanges
that preserve strong attachment sites for the
flexor digitorum superficialis muscle.
Numerous features of the hip, knee, and ankle
indicate that Au. sediba was a habitual biped. In
terms of size and morphology, the proximal and
distal articular ends of the femur and tibia fall
within the range of variation of specimens
attributed to Au. africanus. However, several
derived features in the pelvis link the Malapa

specimens with later Homo. In the os coxa (Fig.
4), Au. sediba shares with Homo a pronounced
acetabulocristal buttress; a more posterior posi-
tion of the cristal tubercle; a superoinferiorly
extended posterior iliac blade, with an expanded
retroauricular area; a sigmoid-shaped anterior in-
ferior iliac spine; a reduced lever arm for weight
transfer between the auricular surface and the
acetabulum; an enlarged and rugose iliofemoral
ligament attachment area; a tall and thin pubic
symphyseal face; and a relatively short ischium
with a deep and narrow tuberoacetabular sulcus.
These features are present in taxonomically un-
assigned postcranial remains from Koobi Fora
(KNM-ER 3228) and Olduvai Gorge (OH 28),
which have been argued to represent early Homo
(20), as well as in early Homo erectus (21). An os
coxa from Swartkrans (SK 3155) has been con-
sidered by some to also represent early Homo
(22) but can be seen to possess the australopith
pattern in most of these features. In addition,
Au. sediba shares with later Homo the human-
like pattern of low humeral-to-femoral diaph-
yseal strength ratios, in contrast to the ape-like
pattern seen in the H. habilis specimen OH 62
(table S2).
Although aspects of the pelvis are derived, the
foot skeleton is more primitive overall, sharing
with other australopiths a flat talar trochlea
articular surface with medial and lateral margins
with equal radii of curvature, and a short, stout,
and medially twisted talar neck with a high
horizontal angle and a low neck torsion angle

Fig. 3. Dental size of a selection of Au. sediba teeth compared
to other early
hominin taxa; see fig. S4 for additional teeth. Dental
measurements were
taken as described by Wood (6). Owing to small sample sizes,
H. habilis and
H. rudolfensis were combined. (A) Upper central incisor
mesiodistal (MD)
length. (B) Upper canine MD length. (C) Lower canine MD
length. (D) Square
root of calculated [MD × BL (BL, buccolingual)] upper third
premolar area.
(E) Square root of calculated (MD × BL) upper second molar
area. (F)
Square root of calculated (MD × BL) lower second molar area.
Measures
were taken on original specimens by D.J.D. for Au. africanus,
Au. robustus,
and Au. sediba. Measurements for Au. afarensis, H. habilis, H.
rudolfensis,
and H. erectus are from (6). P4 is not fully erupted on the right
side of MH1,
therefore measures of the maxillary postcanine dentition are
presented for
the left side only. Dental metrics for Au. sediba are as follows
(MD, BL, in
millimeters): Maxillary: MH1: RI1 10.1, 6.9; LI2 7.7
(damaged), 5.1; RC
9.0, 8.8; LP3 9.0, 11.2; LP4 9.2, 12.1; LM1 12.9, 12.0; LM2
12.9, 13.7;
LM3 13.3, 14.1; MH2: RM3 11.3, 12.9. Mandibular: MH1: LC
8.0, 8.5; RM1
12.5, 11.6; RM2 14.4, 12.9; RM3 14.9, 13.8; MH2: RM1 11.8,
11.1; RM2
14.1, 12.2; RM3 14.2, 12.7; LM3 14.1, 12.5.

RESEARCH ARTICLES
(table S2 and fig. S5). The calcaneus is markedly
primitive in its overall morphology: the bone is
strongly angled along the proximodistal axis,
with the point of maximum inflexion occurring at
an enlarged peroneal trochlea; the lateral plantar
tubercle is lacking; the calcaneal axis is set about
45° to the transverse plane; and the calcaneocu-
boid facet is vertically set and lacks an expanded
posterior projection for the beak of the cuboid
(23).
Discussion. The age and overall morpholo-
gy of Au. sediba imply that it is most likely
descended from Au. africanus, and appears more
derived toward Homo than do Au. afarensis, Au.
garhi, and Au. africanus. Elsewhere in South
Africa, the Sterkfontein cranium Stw 53, dated to
2.0 to 1.5 Ma, is generally considered to represent
either H. habilis (10, 24, 25) or perhaps an
undiagnosed form of early Homo (26). It played
an important role in the assignment of OH 62 to
H. habilis (27). However, the derived cranioden-
tal morphology of Au. sediba casts doubt on the
attribution of Stw 53 to early Homo [see also
(28)]: Stw 53 appears to be more primitive than
MH1 in retaining closely spaced temporal lines;
marked postorbital constriction; a weakly devel-
oped supraorbital torus; narrow, nonprojecting
nasal bones; anterior pillars; marked nasoalveolar

prognathism; medial and lateral expansion of the
frontal process of the zygomatic bone; and
laterally flared zygomatics. If Stw 53 instead
represents Au. africanus, the assignment of OH
62 to H. habilis becomes tenuous. Attribution of
the partial skeleton KNM-ER 3735 to H. habilis
was tentatively based, in part, on a favorable
comparison with OH 62 and on the hypothesis
that there were no other contemporaneous non-
robust australopith species to which it could be
assigned in East Africa (29). As a result, the
interpretation of KNM-ER 3735 as H. habilis
also becomes uncertain.
The phylogenetic significance of the co-
occurrence of derived postcranial features in
Au. sediba, H. erectus, and a sample of isolated
fossils generally referred to Homo sp. indet.
(table S2) is not clear: The latter might repre-
sent early H. erectus, it might sample the post-
cranium of H. rudolfensis (which would then
imply an evolutionary pathway from Au. sediba to
H. rudolfensis to H. erectus), or it might represent
the postcranium of H. habilis [which would sug-
gest that OH 62 and KNM-ER 3735 (two speci-
mens with ostensibly more primitive postcranial
skeletons) do not belong in this taxon]. If the lat-
ter possibility holds, it could suggest a phyloge-
netic sequence from Au. sediba to H. habilis to
H. erectus. Conversely, although the overall post-
cranial morphology of Au. sediba is similar to that
of other australopiths, a number of derived features
of the os coxa align the Malapa hominins with
later Homo (H. erectus) to the exclusion of other
australopiths. Additionally, Au. sediba shares a

small number of cranial traits with H. erectus that
are not exhibited in the H. habilis–H. rudolfensis
hypodigm, including slight postorbital constriction
and convexity of the infraorbital region (18).
Following on this, MH1 compares favorably with
SK 847 (H. erectus) in the development of the
supraorbital torus, nasal bones, infraorbital region,
frontal process of the zygomatic, and subnasal
projection. However, MH1 differs from SK 847 in
its relatively smaller size, the robust glabelar re-
gion, the weakly developed supratoral sulcus, the
steeply inclined zygomaticoalveolar crests with a
high masseter origin, and the moderate canine
juga, all features aligning MH1 with Australopith-
ecus. It is thus not possible to establish the precise
phylogenetic position of Au. sediba in relation to
the various species assigned to early Homo. We
can conclude that combined craniodental and post-
cranial evidence demonstrates that this new spe-
cies shares more derived features with early Homo
than does any other known australopith species
(Table 1 and table S2) and thus represents a candi-
date ancestor for the genus, or a sister group to a
close ancestor that persisted for some time after the
first appearance of Homo.
The discovery of a <1.95-million-year-old
(16) australopith that is potentially ancestral to
Homo is seemingly at odds with the recovery of
older fossils attributed to the latter genus (5) or of
approximately contemporaneous fossils attribut-
able to H. erectus (6, 30). However, it is unlikely
that Malapa represents either the earliest or the
latest temporal appearance of Au. sediba, nor
does it encompass the geographical expanse that

the species once occupied. We hypothesize that
Au. sediba was derived via cladogenesis from
Au. africanus (≈3.0 to 2.4 Ma), a taxon whose
first and last appearance dates are also uncertain
(31). The possibility that Au. sediba split from
Au. africanus before the earliest appearance of
Homo cannot be discounted.
Although the skull and skeleton of Au. sediba
do evince derived features shared with early
Homo, the overall body plan is that of a hominin
at an australopith adaptive grade. This supports
the argument, based on endocranial volume and
craniodental morphology, that this species is
most parsimoniously attributed to the genus
Australopithecus. The Malapa specimens dem-
Fig. 4. Representative ossa coxae, in lateral view, from left to
right, of Au.
afarensis (AL 288-1), Au. africanus (Sts 14), Au. sediba (MH1),
and H. erectus
(KNM-WT 15000). The specimens are oriented so that the iliac
blades all lie in the
plane of the photograph (which thus leads to differences
between specimens in
the orientation of the acetabula and ischial tuberosities). MH1
possesses derived,
Homo-like morphology compared to other australopithecines,
including a relative
reduction in the weight transfer distance from the sacroiliac
(yellow) to hip (circle)
joints; expansion of the retroauricular surface of the ilium (blue
arrows)
(determined by striking a line from the center of the sphere
representing the

femoral head to the most distant point on the posterior ilium;
the superior arrow
marks the terminus of this line, and the inferior arrow marks the
intersection of
this line with the most anterior point on the auricular face);
narrowing of the
tuberoacetabular sulcus (delimited by yellow arrows); and
pronouncement of the
acetabulocristal (green arrows) and acetabulosacral buttresses.
RESEARCH ARTICLES
onstrate that the evolutionary transition from a
small-bodied and perhaps more arboreal-adapted
hominin (such as Au. africanus) to a larger-
bodied, possibly full-striding terrestrial biped
(such as H. erectus) occurred in a mosaic fashion.
Changes in functionally important aspects of
pelvic morphology, including a reduction of the
sacroacetabular weight-bearing load arm and
enhanced acetabulosacral buttressing (reflect-
ing enhancement of the hip extensor mecha-
nism), enlargement of the iliofemoral ligament
attachment (reflecting a shift in position of the
line of transfer of weight to behind the center of
rotation of the hip joint), enlargement of the
acetabulocristal buttress (denoting enhancement
of an alternating pelvic tilt mechanism), and re-
duction of the distance from the acetabulum to
the ischial tuberosity (reflecting a reduction in the
moment arm of the hamstring muscles) (20, 32)
occurred within the context of an otherwise aus-

tralopith body plan, and seemingly before an
increase in hominin encephalization [in contrast
to the argument in (33)]. Relative humeral and
femoral diaphyseal strength measures (table S2)
also suggest that habitual locomotor patterns in
Au. sediba involved a more modern human-like
mechanical load-sharing than that seen in the
H. habilis specimen OH 62 (34, 35). Mosaic evo-
lutionary changes are mirrored in craniodental
morphology, because the increasingly wide spacing
of the temporal lines and reduction in post-
orbital constriction that characterize Homo first
appeared in an australopith and before significant
cranial expansion. Moreover, dental reduction,
particularly in the postcanine dentition, preceded
the cuspal rearrangement (wide spacing of post-
canine tooth cusps) that marks early Homo.
The pattern of dental eruption and epiphyseal
fusion exhibited by MH1 indicates that its age at
death was 12 to 13 years by human standards,
whereas in MH2 the advanced degree of occlusal
attrition and epiphyseal closure indicates that it
had reached full adulthood (SOM text S1). Al-
though juvenile, MH1 exhibits pronounced devel-
opment of the supraorbital region and canine juga,
eversion of the gonial angle of the mandible, and
large rugose muscle scars in the skeleton, all in-
dicating that this was a male individual. And, al-
though fully adult, the mandible and skeleton of
MH2 are smaller than in MH1, which, combined
with the less rugose muscle scars and the shape of
the pubic body of the os coxa, suggests that MH2
was a female. In terms of dental dimensions, MH1
has mandibular molar occlusal surface areas that
are 10.7% (M1) and 8.1% (M2) larger than those

of MH2. Dimorphism in the postcranial skeleton
likewise is not great, though the juvenile status of
MH1 tends to confound efforts to assess adult
body size. The diameter of the proximal epiphysis
for the femoral head of MH1 (29.8 mm) is ap-
proximately 9.1% smaller than the superoinferior
diameter of MH2's femoral head (32.7 mm). It is
likely that MH1 would have experienced some
appositional increase in joint size before matu-
rity, thus this disparity would probably have de-
creased somewhat. The distal humeral epiphysis
of MH1 is fully fused and its articular breadth
(35.3 mm) is only marginally larger than that of
MH2 (35.2 mm). Thus, although the dentition
and postcranial skeleton are at odds in the de-
gree of apparent size differences, the overall
level of dimorphism, if these sex attributions are
correct, appears slight in the Malapa hominins
and was probably similar to that evinced by mod-
ern humans.
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they represent homologous structures. In specimens of
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KNM-WT 15000) have crests that are more strongly
developed than those of modern humans, none exhibit
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Hominidae, G. Giacobini, Ed. (Jaca Books, Milano, Italy,
1989), pp. 167–173.
30. L. Gabunia, A. Vekua, Nature 373, 509 (1995).
31. T. D. White, in Paleoclimate and Evolution with Emphasis
on Human Origins, E. S. Vrba, G. H. Denton,
T. C. Partridge, L. H. Burckle, Eds. (Yale Univ. Press,
New Haven, CT, 1995), pp. 369–384.
32. J. T. Stern Jr., R. L. Susman, Am. J. Phys. Anthropol. 60,
279 (1983).
33. C. O. Lovejoy, Gait Posture 21, 113 (2005).
34. C. Ruff, Am. J. Phys. Anthropol. 138, 90 (2009).
35. It is possible that the more Homo-like humeral-to-femoral
diaphyseal strength ratios in Au. sediba reflect a
relative reinforcement of the femoral diaphysis in the
context of femoral elongation (resulting in longer
bending-moment arms) without a change in locomotor
behavior. At present, we are unable to directly assess
the absolute and relative length of the femur in
Au. sediba.
36. Y. Rak, The Australopithecine Face (Academic Press,

New York, 1983).
37. M. R. Lague, W. L. Jungers, Am. J. Phys. Anthropol. 101,
401 (1996).
38. R. R. Skelton, H. M. McHenry, J. Hum. Evol. 23, 309
(1992).
39. M. Collard, B. Wood, Proc. Natl. Acad. Sci. U.S.A. 97,
5003 (2000).
40. H. F. Smith, F. E. Grine, J. Hum. Evol. 54, 684
(2008).
41. We thank the South African Heritage Resources Agency
for the permits to work at the Malapa site; the Nash
family for granting access to the Malapa site and
continued support of research on their reserve; the South
African Department of Science and Technology, the South
African National Research Foundation, the Institute for
Human Evolution, the Palaeontological Scientific Trust,
the Andrew W. Mellon Foundation, the AfricaArray
Program, the U.S. Diplomatic Mission to South Africa,
and Sir Richard Branson for funding; the University of the
Witwatersrand’s Schools of Geosciences and Anatomical
Sciences and the Bernard Price Institute for
Palaeontology for support and facilities; the Gauteng
Government, Gauteng Department of Agriculture,
Conservation and Environment and the Cradle of
Humankind Management Authority; E. Mbua, P. Kiura,
V. Iminjili, and the National Museums of Kenya for access
to comparative specimens; Optech and Optron; Duke
University; the Ray A. Rothrock Fellowship of Texas
A&M University; and the University of Zurich 2009 Field
School. Numerous individuals have been involved in the
ongoing preparation and excavation of these fossils,

including C. Dube, B. Eloff, C. Kemp, M. Kgasi,
M. Languza, J. Malaza, G. Mokoma, P. Mukanela,
T. Nemvhundi, M. Ngcamphalala, S. Jirah, S. Tshabalala,
and C. Yates. Other individuals who have given
significant support to this project include B. de Klerk,
C. Steininger, B. Kuhn, L. Pollarolo, B. Zipfel, J. Kretzen,
D. Conforti, J. McCaffery, C. Dlamini, H. Visser,
R. McCrae-Samuel, B. Nkosi, B. Louw, L. Backwell,
F. Thackeray, and M. Peltier. T. Stidham helped construct
the cladogram in fig. S3. J. Smilg facilitated computed
tomography scanning of the specimens. R. Clarke and
F. Kirera provided valuable discussions on these and
other hominin fossils in Africa.
Supporting Online Material
www.sciencemag.org/cgi/content/full/328/5975/195/DC1
SOM Text 1 to 4
Figs. S1 to S5
Tables S1 and S2
References
19 November 2009; accepted 26 February 2010
10.1126/science.1184944
RESEARCH ARTICLES
1
CorreCtions & CLarifiCations
www.sciencemag.org sCiEnCE erratum post date 17
deCemBer 2010

Erratum
Research Articles: “Australopithecus sediba: A new species of
Homo-like Australopith
from South Africa” by L. R. Berger et al. (9 April, p. 195). In
the legend of Fig. 3, the
mesiodistal diameter of the RM2 of the mandible of the adult
individual MH2 should be
13.1 mm (not 14.1 mm). In Fig. 4, the specimen number of the
pelvis of Australopithe-
cus afarensis (Lucy) should be A.L. 288-1 (not A.L. 228-1).
These errors do not affect the
Research Article’s conclusions.
CorreCtions & CLarifiCations
Post date 17 December 2010
R E P O R T S
However, the absence of abundant lithic as-
semblages at these Hata archaeology sites
requires explanation.
At the nearby Gona site, abundant Oldowan
tools were made and discarded immediately
adjacent to cobble conglomerates that ofïered
excellent, easily accessible raw materials for
stone-tool manufacture. It has been suggested
thai the surprisingly advanced character of this
earliest Oldowan technology was conditioned
by the ease of access to appropriate fine-grained
raw materials at Gona {10). Along the Karari

escarpment at Koobi Fora (13). the basin mar-
gin at Fcjej ( 14). and the lake margin at Olduvai
Gorge {12), hominids also had easy access to
nearby outcrops of raw material. In contrast, the
diminutive nature ofthe Oldowan assemblages
in ilie lower Omo [made on tiny quartz, pebbles
{15)] was apparently conditioned by a lack of
available large clasts.
Tlie situation on the Hata lake margin was
even more difficult for early toolmakers. Here,
raw materials were not readily available becau.se
of the absence of streams capable of carrying
even pebbles. There were no neiirby basalt out-
crops. The absence of locally available raw ma-
terial on the flat featureless Hata lake margin
may explain the absence of lithic artifact con-
centrations. The bone modification evidence
demonstrates that early hominids were trans-
porting stone to Ihe site of carcass manipulation.
The paucity of evidence for lithic artifact aban-
donment at these sites suggests that these early
hominids may have been curating their tools
(cores and flakes) with foresight tbr subsequent
use. Indications of tool curation by later homi-
nids have been found at the more recent Pleis-
tocene sites of Koobi Fora [Karari escarpment
versus Ileret (¡3)] and Swartkrans [polished
bone tools in a single repository {16)],
Additional research into the Hata beds
may allow a determination of whether Ihe
butchery is related to hunting or scavenging.
The Bouri discoveries show that the earliest
Pliocene archaeological assemblages and
their landscape patterning are strongly condi-

tioned by the availability of raw material.
They demonstrate that a major function ofthe
earliest known tools was meat and marrow
processing of large carcasses. Finally, they
e.xtcnd this pattern of butcher)' by hominids
well into the Pliocene,
References and Notes
1. B. Asfaw et ai. Science 284, xxx (1999).
2. N. J. Hayward and C. J. Ebinger, Tectonics I S , 244
(1996).
3. ] . E. Kalb et ai. Nature 298, 17 (1982). Eleven years
later, J. E, Kalb et ai [Newsl. Stratigr. 29, 21 (1993)]
tollowed Clark et al. (4) in reversing Daka/Bodo
Member order,
4. J. D. Clark e i ai. Nature 307, 423 (1984).
5. J. D. Clatk e£ ai., Sc/ence 264, 1907 (1994).
6. P. R, Renne. C. WoldeCabrieL W. K. H a n , G. Heiken,
T. D. White, Ceo/. Soc. Am. Bull., in press,
7. The age of this standard is now known to be slightly
older [28.02 Ma {17)]. but comparison with previous
data (for example, from the Cona) is facilitated by
retaining the standard age of 27.84 Ma. A table of the
Ar isotopic data is available at www.sciencemag.org/
feature/data/991110.shl.
8. F. J. Hilgen, Earth Planet. Sei. iett. 107, 249 (1991).
9, The sedimentation rate inferred is conservative be-
cause comparison of the *'Ar/*^Ar age w i t h the age

of 2.6 Ma (8} for the Gauss/Matuyama boundary
more properly requires the use of the older age of the
standard (28.02 Ma) and indicates an - 1 0 % greater
sedimentation rate.
10. S. Semaw e i ai. Nature 385, 333 (1997),
11. T. D. White, Prehistoric Cannibalism at Mancos
SMTUMR-2346 (Princeton Univ, Press, Princeton, NJ,
1992); L R. Binford, Bones: Ancient Men and Modern
Myths (Academic Press, New York, 1981): R, J. Blu-
menschine,/ Hum. Evol. 29, 21 (1995); S, D, Capaldo
and R. J. Blumenschine, Am. Antiq. 59, 724 (1994),
12. R. J. Btumenschine and F. T, Masao, y. Hum. Evoi 2 1 ,
451 (1991).
13. G, L. Isaac, Ed., Koobi Fora Research Project Volume 5:
Plio-Pleistocene Archaeology (Clarendon, Oxford,
1997).
14. B, Asfaw et at.J. Hum. Evoi 2 1 . 137 (1991).
15. F. C. Howell, P. Haeserts, J. de Heinzelin, ibid. 1 6 , 6 6 5
(1987),
16. C. K. Brain, Ed., Swartkrans: A Cave's Chronicle of Early
Man. vol. 8 of Transvaal Museum Monograph Series
(Transvaal Museum, Pretoria, 1993),
17. P. R. Renne e i ai. Chem. Ceoi 145. 117 (1998).
18. The Middle Awash paleoanthropobgical project is
multinational {13 countries), w i t h interdisciplinary
research codirected by B. Asfaw, Y, Beyene, J. D. Clark,
T, D. White, and G. WoldeCabriel. The research re-

ported here was supported by NSF, the Ann and
Gordon Getty Foundation (8erkeley Geochronology
Center), and the Institute of Geophysics and Plane-
tary Physics of the University of California and the
Earth Environmental Sciences Division at Los Alamos
National Laboratory. Additional contributions were
made by the Graduate School, the Office for Ad-
vancement of Scholarship and Teaching, and the
Department of Geology at Miami University. We
thank the Ethiopian Mapping Agency and the NASA
Goddard Space Flight Center for imagery. We thank
H. Gilbert for fieldwork and for work on the illustra-
tions. D. Brill made the photographs and G. Richards
and B. Plowman at the University of Pacific made the
scanning electron microscope (SEM) image. T. Larson
provided invaluable field and laboratory geology sup-
port. A. Defleur assisted in field survey and excava-
tions at BOU-VP-11. We thank H. Saegusa for pro-
boscidean Identifications, D. DeGusta for primate
identifications and excavations at BOU-VP-12/1, and
F. C. Howell for carnivore identifications. We thank
O. Lovejoy, G. Suwa, and 6. Asfaw for helpful com-
ments. We thank the Ethiopian Ministry of Informa-
tion and Culture, the Centre for Research and Con-
servation o l the Cultural Heritage, and the National
Museum of Ethiopia. We thanü the Afar Regional
Government and the Afar people of the Middle
Awash for permission and support. We thank the
many individuals who contributed to the camp,
transport, survey, excavation, and laboratory work
that stands behind the results presented.
25 February 1999; accepted 30 March 1999
Australopithecus garhi: A New

Species of Early Hominid
from Ethiopia
Berhane Asfaw,̂ Tim White,^* Owen Lovejoy,̂
Bruce Latimer/-^ Scott Simpson,^ Cen Suwa^
The lack of an adequate hominid fossil record in eastern Africa
between 2 and
3 million years ago (Ma) bas hampered investigations of early
hominid phy-
logeny. Discovery of 2,5 Ma hominid cranial and dental remains
from the Hata
beds of Ethiopia's Middle Awash allows recognition of a new
species of Aus-
tralopithecus. This species is descended from Australopithecus
afarensis and is
a candidate ancestor for early Homo. Contemporary postcranial
remains feature
a derived humanlike humeral/femoral ratio and an apelike upper
arm-to-lower
arm ratio.
The succession of early hominid genera and
species indicates diversification into at least
two distinci adaptive patterns by - 2 . 7 Ma, A
meager east African hominid record hetween
2 and 3 Ma has caused the pattern and pro-
'Rift Valley Research Service, Post Office Box 5717,
Addis Ababa, Ethiopia. ^Laboratory for Human Evolu-
tionary Studies, Museum of Vertebrate Zoology, and
Department of Integrative Biology. University of Cal-
ifornia at Berkeley, Berkeley, CA 94720, USA, 'Depart-
ment of Anthropology and Division of Biomédical
Sciences, Kent State University, Kent OH 44242, USA.
'Cleveland Museum of Natural History and ^Depart-

ment of Anatomy, School of Medicine, Case Western
Reserve University, Cleveland, OH 44106. USA. ''Uni-
versity Museum, University of Tokyo, Hongo, Bunkyo-
ku, Tokyo. 113-0033, Japan.
•To whom correspondence shouEd be addressed. E-
mail: [email protected],berkeley.edu
cess ol'this diversification to remain obscure.
The Aitstrahpirheni.'i afarensis (3.6 to 3.0
Ma) to A. aeihiopicus (2,6 Ma) to A. hoi.sci
(2,3 to 1.2 Ma) species lineage is well cor-
roborated by craniodenial remains. In con-
trast, a suggested relationship between A. a/a-
ren.si.s and early Homo has previously been
evidenced only by relalively uninfoniuilive
isolated teeth (/). a palate {2). and a temporal
fragment (3).
The recovery ol" hominid lemains from ilie
Hala (abbreviation of Hatayae) Member of thi..-
Bouri honnalioii -MMS snh îtantially ti) the in-
ventor)'oCtossi Is l>earini;on those phyioiieneiK'
issues. These remains comprise craniotiental
and postcraniai elements trom several areas in
the Middle Awash. The first of tliese was dis-
covered in ty')O at Matabaietu and Gamedah.
R E P O R T S
Biochronology and Ar/Ar daring place these

remains at —2.5 Ma. They include a small left
parietal fragment (GAM-VP-1/2) and an eden-
tulous left mandible corpus from Gamedah
(GAM-VP-1/l). as well as a distal left humérus
fTom Matabaietu (MAT-VP-1/1). It is impossi-
ble to attribute the humérus and parietal frag-
ments to a genus. However, tbe small, fluvially
abraded Gamedah mandible retains looth roots
and corpus contours. Tbese demonstrate that it
is not a robust Aitslralopiihccus.
Tt was not until 1996 - 199ÍÍ that we recov-
ered addilional hominid remains of compara-
ble antiquity west of the modem Awash, at
Bouri. The proximal half of an adult hominid
ulna (BOU-VP-lI/1) was found on the sur-
face of the Hata beds by T. Assebework on 17
Novetnber 1996. On 30 November. White
found a proximal femur and associated fore-
arm elements of a smaller individual, --I00
m to tbe WNW (BOU-VP-12/1 A-G). Sieving
and excavation revealed additional portions
of tbis individual's femur in situ. 1 m above
a 2.496 Ma voleanie ash. in a horizon with
abundant catfish remains and medium-sized
bovid fossils, the latter bearing cut marks (-̂ i).
Tbis partial hominid skeleton includes lairly
complete shalts oi' a left femur and tbe right
hinneruii. radius, and ulna. A partial fibular
shaft, a proximal foot phalanx, and tbe base of
the anterior portion of the mandible were also
found. There is no evidence that these remains
represent more tban one individual. Except for
the in situ distal femoral shaft segment, all were
surface finds lying within 2 m of one another.

All are similarly preserved. Lengths can be
accurately estimated for the phalatix, the femur,
and the three arm elements. The foot phalanx is
similar to remains of A. afarensis in size,
length, and curvature. The mandible does not
retain diagno.stic morphology. No associated
hominid teeth were found on the surface or in a
large excavation.
Further search of the same —2.5 Ma horizon
led 10 the discovery. 278 m farther NNW. of a
partial bominid cranium ( BOU-VP-12/130) on
20 November 1997 by Y. Haile-Selassie (Fig.
1). Anotlier individual's crested cranial vault
fragment (BOU-VP-12/87) was found 50 m
soulb of the BOU-VP-12/1 skeleton excava-
rion. At a more northerly locality in the Esa
Dibo area —9 km away. A. Defleur found a
fairly complete mandible, with dentition, of
another hominid individual (BOU-VP-17/1) on
17 November 1997. An additional hotninid hu-
meral shaft (BOU-VP-35/1) was found -1 km
farther north of the location of the mandible, on
4 December 1998, by D. DeGusta. On bioehro-
nologieal grounds, these Esa Dibo specimens
are about the same age as the more southerly
cluster of hoininid remains at tiouri localities
11 and 12(4).
Great uncertainty has continued to con-
found the origin oi'Homo because of a laek of
evidence from the intei'val between 2 and 3
Ma (5). The 2.5 Ma Bouri Hata hominids
bear directly on tbese issues. In addition, they
are closely associated with behavioral evi-

dence of lithic technology (4 ). Aii.stralopithe-
cu.s africumis from South Africa is roughly
contemporary with the Hata remains. In east-
em Africa. A. ai'ihiopicns and at least one
other putative lineage ancestral to early
Homo are contemporaries in (he Turkana Ba-
sin. The BOU-VP-12/130 cranial remains
represent no previously named species. Only
the recovery of additional specimens witb
a.ssoeiated crania and dentitions may allow
tbe Bouri postcrania to be positively attribut-
ed to this new taxon. Therefore, the new
species described below is established strictly
on tbe basis of craniodental remains.
The following is a description of Attsira-
topiihecus garhi, based on the BOU-VP-12/
130 specimen: order. Primates Linnaeus
1758; suborder. Antbropoidea Mivart 1S64:
genus. Australopithecus DART 1925; and
species. Amiraiopithecus garhi.
£tymology. Tbe word garhi means "sur-
prise" in tbe Afar language.
Holotj'pe. ARA-VP-12/130 is an associated
set of cranial fragments cotnprising the frontal,
parietals, and maxilla with dentition. It was
found by Y. Haile-Selassie on 20 November
1997. Tbe holotype is housed at the National
Museum of Ethiopia. Addis Ababa.
Locality. Bouri Vertebrate Paleontolo-
gy locality 12 (BOU-VP-12) is on the east-
ern side of the Bouri peninsula, west of the

modem Awash River, in the Middle Awash
paleoanthropological sttidy area. Afar depres-
Fig. 1. Cranial parts of BOU-VP-12/130. (Top) Superior view of
the original fossil. Nonstandard
orientation (rotated posteriorly - 1 0 ° from Frankfurt
horizontal) to show maximum anatomy. (Bottom)
Lateral view of casts to show cranial and maxillary profiles.
Note that neither Frankfurt horizontal nor
placement of the maxilla relative to the vault can be accurately
determined and that reconstructed
portions (indicated by oblique lines) are speculative. Photos
©David L. Brill 1999Atlanta.
630 23 APRIL 1999 VOL 284 SCIENCE www.sciencemag.org
R E P O R T S
sion, Ethiopia. Tlie BOU-VP-I2/I30 holotype
was tbund at 10^15.6199'N, 40°33.8445'E. at
-'5Si) m elevation.
Hori/on and associations. The holotype
was recovered from silty clays within 2 m of
the top ofthe Maoleem vitric tuff, whieh has
been dated to 2.496 Ma by Ar/Ar. Vertebrate
fossils, including additional hominids, were
Ibund at the same stratigraphie horizon on
nearby outcrops (4).
Diagnosis.. Au.stralopiihecus garhi is a
species of .4uslralopilhccus distinguished
from other hominid species by a combination
of characters presented in fable I. It is dis-

tinguished from .i. ajwcnsis by its absolutely
larger postcanine dentition and an upper third
premolar morphology with reduced niesio-
buccal enamel line projectioEi and less occlu-
sal asymmetry, .^mu-alopilhccus ^arlii lacks
the suite of derived dental, facial, ¡md cranial
features shared by A. aelhiopicus, A. robus-
Im, and A. hoisei. Ausfnilnpithecm garhi is
di.stinguished trom A. africamis and other
early Homo species by its primilive froiitül.
facial, palatal, and subnasal morphology.
•*-Dciital description. The postcanine den-
tal si/L' is remarkable, at or beyond tiie known
nonrobusl and .-). rahusltis extremes (I-ig. 2).
The anterior dentition is also large, with 11
and canine breadths equivalent to or cxceed-
Table 1. List of characters. Listed are characters widely used in
consideration of
hominid pbylogenetics (IT. 13) that are preserved on the BOU-
VP-12/130
bolotype cranium. Because of arbitrary boundaries of presence
or absence
criteria, variability within species, limited sample sizes, and
possible correlation
between features, we caution against a numerical ctadistic
application of these
tabulated data, Ratber, this character list is meant to
demonstrate the phenetic
status of the single known A. garhi specimen with respect to
features used to
evaluate early hominid fossils. Note that despite tbe large
postcanine dentition,

no shared derived characters link A. garhi with A. robustus or
A. boisei. The "early
Homo" column comprises specimens assigned by various
authors to both H.
habilis and H. rudolfensis. Abbreviations are as follows: mod.,
moderate; asym.,
asymmetric; disp., disparate; sym., symmetric; rect.,
rectangular; para., parabolic;
var., variable; conv,, convergent; div., divergent; ant., anterior;
prom,, prominent;
proc, procumbent: cont, continuous; interm., intermediate.
Canine to postcanine ratio
Incisor to postcanine ratio
Postcanine absolute size
UP3 occlusal outline
UP3 mesiobuccal line extension
Postcanine PM/M cusp wear
Canine lingual sbape
Premolar molarizatlon
Enamel thickness
Ant. vertical thickness
Dental arcade sbape
Posterior dental arcade
Ant, depth
UI2/UC diastema
Incisor alveoli relative t o bicanine line
C jugum
Ant. pillars
Inferolateral nasal aperture margin
UI2 root lateral to nasal aperture
Canine fossa
Maxillary fossula

Anterior zygomatic root position
Zygomattcoalveolar crest
ciivus contour
Subnasal prognathism
Incisor procumbency
Subnasal to intranasal contours
Separation of vomeral/ant. septal
insertion
Lateral ant. facial contour
Facial dishing
Frontal trigon
Costa supraorbitalis
Temporal line's frontal convergence
Postorbital constriction
Sagittal crest in male
Relative size of posterior temporalis
Parietal transverse expansion/tuber
Parietomastoid angle
Cranial capacity
A.
afarensis
large
large
mod.
asym.
frequent
disp.
asym.
none
moderately

thirk
Ll 111.1^
thin
rect.
conv.
shallow
common
ant.
prom.
absent
sharp
lateral
present
absent
M l
arched
convex
strong
proc.
discrete
strong
bipartite
absent
present
present
mod.
mod.
present
large
absent
flared
small

A. garhi
(n=^)
large
smaller
large
more
oval
absent
disp.
asym.
minor
tbick
thin
rect.
div.
shallow
present
ant.
prom.
absent
sharp
in line
present
absent
M1-P4
arcbed
convex
strong
proc.
discrete
strong

bipartite
absent
present
present
mod.
mod.
present
interm.
absent
weak
small
Early Homo
Dentition
large
large
mod.
more oval
rare
disp.
asym.
minor
thick
Paiate
thin
para.
div.
deep
rare
var.
Lower face

var.
absent
sharp
medial
var.
absent
M1-P4
arched
flat/convex
var.
var.
discrete
usually strong
var.
absent
Vault
absent
torus
weak
mod.
rare
interm.
present
weak
enlarged
Males of
A. africanus
large
smaller
mod. to large
more oval

rare
disp.
asym.
minor
thick
thin
var.
div.
var.
absent
ant.
prom.
present
var.
medial
present
absent
M1-P4
var.
flat
var.
var.
var.
weak
var.
absent
absent
interm.
weak
mod.
rare

interm.
absent
weak
small
A.
aethiopicus
(n-l)
unknown
smaller?
large
oval
absent
flat
unknown
pronounced
hyperthick
thick
recL
conv.
shallow
absent
in line
weak
absent
blunt
medial
absent
absent
P4
weak

concave
strong
proc.
cont.
weak
straight
dished
present
present
strong
marked
present
large
absent
flared
small
A. robustus
small
small
large
oval
absent
flat
more sym.
pronounced
hyperthick
tbick
para.
div.
usually deep

absent
in line
weak
present
var.
medial
absent
present
P4-P3
var.
flat to concave
weak
more vertical
cont
weak
straight
dished
present
present
strong
marked
present
small
absent
weak
slightly
enlarged
A. boisei
small
small
large

oval
absent
flat
more sym.
pronounced
hypertbick
thick
para.
div.
deep
absent
in line
weak
absent
var.
medial
absent
absent
P4/M1-P3
var.
flat to concave
weak
more vertical
var.
weak
straight
dished
present
present
strong
marked

present
small
absent
weak
slightly
enlarged
vvww.sclencemag.org SCIENCE VOL 284 23 APRIL 1999 6 3 1
R E P O R T S
ing those of their largest known Australo-
pithecus and early Homo homologs. Thus,
despite exceptional postcanine size, dental
proportions of the holotype deviate markedly
from the robust Australopithecus condition.
The canine-to-premolar/molar size ratios are
comparable to those of .̂ i. afarensis., A. afri-
canus, and early Homo. Relative canine to
incisor alveolar length is most similar to that
OÍA. africanus. Postcaiiine wear, with devel-
oped angular facets and retention of buccal
cusp saliency. differs distinctively from the
robust Australopiihecus pattern. The upper
P3 is more derived than that of .4. afarensis
and most A. africanus specimens in e.xiiihit-
ing a reduced mesiobuccal crown quadrant
and a weak transverse crest. The hiiccolingual
narrowing of prcmolars and first molars often
seen in early Homo is absent.
Cranial description. The lower face is
prognathic. with procumbent incisors. Canine
roots arc placed well lateral to the nasal

aperture margin. The premaxillary surface is
separated from the nasal floor by a blunt
ridge and is transversely and sagittally con-
vex. The palate is vertically thin (~3 mtn at
M1/M2 midline). The zygomatic roots origi-
nate above P4/MI. The dental arcade is U-
shaped, with slightly divergent dental rows
(Fig. 3). The temporal lines encroach deeply
on the frontal, past the midsupraorbital posi-
tion, and probably met anterior to bregma.
The postglabellar frontal squama is depressed
in a frontal trigon. The localized frontal sinus
is limited to the medial one-third of the su-
praorbital surface. Postorbital constriction is
marked. The parietal bones have a well-
formed, bipartite, anteriorly positioned sagit-
tal crest that divides above lambda. An endo-
cast was made from the aligned parietals and
frontal and was completed by sculpting by R.
lloUoway. Crania! capacity was about 450
cm', as measured b' water displacement.
Taxonomic discussion. There is no cunent
agreement about how many pre-erecft/5 Homo
species should be recognized or even on how
the genus Homo should be defined. The tradi-
tional conservative definition emphasizes adap-
tive plateau. Ironically, by this definilion. the
early Homo species H. rudolfensis and H. ha-
bilis miglit be better placed in Australopithecus.,
as this would affiliate the major adaptive break-
throughs in anatomy and behavior that charac-
terize H. erectus (ergaster) with the earliest
defined occurrence oï Homo. fA. garhi proves
to be the exclusive ancestor of the Homo elade

(see discussion below), a cladistic classification
might assign it to genus Homo. Here we provi-
sionally adopt the conservative, grade-sensitive
alternative, emphasizing its small brain and
large postcanine dentition by assigning the new
Bouri species to .4ustralopitÍK'ctis. This attribu-
tion as well as our diagnosis and description
may require emendation when additional indi-
viduals representing the species are recovered
and firm postcranial associations are estab-
lished (rt).
Although the Bouri Hata postcrania cannot
presently he assigned to the new species A.
garfti., tliey illuminate a.spects of hominid evo-
lution. The past few years have witnessed a rash
of attempts to estimate early hominid limb
length proportions from fragmentary and unas-
sociated specimens. These specimens have
been used to generate a variety of ftinctional
and phylogenetic scenarios. Accurate estimates
of the limb proportions of early hominids. how-
ever, must be confined to the very lew speci-
mens that actually preserve relevant elements,
such as the A.L. 288-1 ("Lucy") specimen and
KNM-WT 15000. The new Bouri VP-12/1
specimen is only the third Plio-PIoistocene
hominid to provide reasonably accurate limb
length proportions. The Olduvai Hominid 62
specimen of Homo hahilis has been erroneously
argued to show humerus-to-femur proportions
more primitive than those of "Lucy" (7, (V), but
its femur length cannot be accurately estimated.
Other studies of limb proportions in early Aus-

tralopiiiwcus species are based on unassociated
joints and not on actual (or even estimated)
limb lengths (7).
The postcranial remains recovered from
BOU-VP-11, -12, and -35 cannot be conclu-
sively allocated to taxon. The BOU-VP-12/1
specimen features a humanlike humeral/fcm-
orai ratio (Fig. 4). This ratio may be an
important derivation relative to A. ajarensis.
because it marks the earliest known appear-
ance of the relative femoral elongation that
characterizes later hoininids. However, as in
A. afarensis, the specimen's brachial index is
Canin« Breadth
BOU-VP-12/130 •
I—I m
10 11 12 13 14 15 mm 12 13 IS 16 17 IB 19 20 mm
1.2-
Helative Canine Breadth
2.2-
Helaüve 11 to C Alveolw LengthFig. 2. Dental size of A. garhi
compared
with other early hominid taxa and speci-
mens. (A) Canine breadth for various taxa.
(B) The square root of calculated (MD X
BL) premolar area. (C) Tbe square root of
calculated (MD x BL} second molar area.

(D) Canine breadth relative t o postcanine
tooth size for various taxa. (E) Anterior
alveolar length (mesial II t o distal C) rela-
tive t o postcanine tooth size. In (A) tbrough
(C), taxon means, standard deviations,
ranges, and sample sizes (in parentheses)
are given. All measures were taken by T.W.
and G.S. on originals except for A.L. 444-2
and A.L 417-1 (A. afarerisis) and A.L. 666-1
(Homo), which are from (2. 14). Dental metrics for the BOU-
VP-12/130 specimen are as follows (XX broken; parentheses =
estimate; mesiodistal
measure reported first, followed by buccolingual): RII XX,
(9.2); R12 6.9, 6.8; RC 11.6.12.9; RP3 (11.0), 16.0; RP4XX,
XX; RMl XX, XX; RM2 (14.4), (17.7);
RM3 (15.2). 16.9; LÍ2 6.7, 7.0; LC 11.7, 12.9; LP3 (11.4), 16.0;
LP4 (11.4). 16.0; LMl (14.4), (16.5), D , A. afarensis: O , A.
africanus; A, Horr)o; • , A.
robustus: A, A. boisei • , BOU-VP-12/130,
I t - C - l1-C..'tM2 Area
632 23 APRIL 1999 VOL 284 SCIENCE www.sciencemag.org
R E P O R T S
apelike. This suggests thai upper arm-to-
lower arm ratios persisted into the basal
Pleistocetie and that ihc first hominid with
modern forearm proportions was probably
ihmo vrectus {ergasicr). Because the A. afa-
rensis forearm was also long relative to both
the humérus and femur, the femur must have
elongated bctbri; Ibreami shortening in early

iiominids.
Ihc BOU-VP-11 ulna is from a larger
individual, as is the BOU-VP-35/1 humeral
shaft (estimated total humeral length ^ 310
to 325 mm). The latter is absolutely longer
than the humenis of BOU-VP-12/1 but is less
rugose and probably bore a smaller deltopec-
toral crest. These differetices (in both size and
mgosity) are well within the species ranges of
extiint liominoids. If both luimcri represent
the same taxon. they could reflect sexual
dimorphi.sm. whieh would be comparable to
that currently seen in A. afarensis. However,
it is perilous to speculate on differences be-
tween only two specimens as they may reflect
only fluctuating intraspeeific variation in
morphology and body mass.
The few and fragmentary nonrobust Tur-
kana Basin hominids that span the 2.7 to 2.3 Ma
time range are similar lo the Uouri specimens in
both size and aspects of morphology. Postca-
nitie dental arcade length of BOU-VP-12/130 is
equivalent to that ofOmo 75-14. whereas indi-
vidual teeth of the smaller Middle Awash man-
dibles (CiAM-VP-l/l and BOU-VP-17/1) are
comparable in size to the smaller specimens of
the Omo nonrobust collection. It is also impor-
tant that BOU-VP-1III exhibits a derived lower
P3 morphology (/) most similar to the Omo
nonrobust and early Homo conditions and a
dental arcade shape concordant with thai of the
holotype of ^. garhi.

On the basis of size. BOU-VP-12/130 is a
male. The eraniodenta) size dimotphism doc-
umented for the closely related A. afarensis
and A. boisei therefore predicts smaller indi-
viduals in A. garhi. The biochronologically
contemporary and morphologically compati-
ble BOU-VP-17/] and GAM-VP-l/1 speci-
tnens are considerably smaller and may be
females. This would suggest a shift in either
or both body and dentognathic sizes to aver-
ages greater than in A. afarensis. More spec-
imens are needed to test this hypothesis.
The diseoveiy of/l. ^arhi provides a strong
test of many phylogenetic hypotheses that have
addressed the relationships among Plio-Pleisto-
cene hominid taxa. The Soutli African species
A. africanus was once widely considered to be
the most primitive hominid. Discoveries oí A.
afarensis at Hadar and Laetoli displaced A.
africanus. This more primitive sister species (.-J.
afarensis) was in turn stipplaiitcd when the
increasingly older and more primitive sister
taxa A. anamensis ( 9) and ArdipiihecLts raniiihi.-i
(¡0) were identified. However, the geometry of
posi-iifarcnsis hominid phylogeny continues to
be the focus of debate.
The position of .1. africanus relative to the
emergence of the genus Homo has been par-
ticularly difficult to resolve, even in the face
of unduly elaborate phylogenetic analyses
( / / ) . One reason for this dillkulty is the
fundamental disagreement on whether early
Homo comprises one sexually dimorphic {//.

Fig. 3. The most complete palates of A. afarensis (A.L 200-1a;
canine reset) (A) and A. boisei
(OH-5) (B) compared with that of A. garhi (C and 0). The
photograph (©David L Brill 1999Atlanta)
vi/as mirror-imaged on midline. Australopithecus garhi has
relatively large canines like A. afarensis
and absolutely large but morphologically nonrobust premolars
and molars. Drawings ©L. Cudi.
Fig, 4. Probable stages in the progressive differ-
entiation of hominid long bone proportions (all
bones shown to the same scale). The humérus
(top), antebrachium (middle), and femur (bot-
tom) are of about equal length in chimpanzees
(Pan). Modern bumans differ in two primary
ways. Although our humérus is virtually the same
length, the femur is elongated and the antebra-
chium is shortened. These changes appear to have
emerged fully by 1.5 Ma in H. erectus [all three
limb segments are virtually complete in KNM-ER-
15000 (75)]. On the basis of the other two partial
skeletons in whicb long bone length can now be
reliably estimated, the modern human pattern
appears to have emerged In two stages: (i) elon-
gation of the femur, which is intermediate in
length relative to the humérus in A.L 288-1 but
exhibits modern proportions in BOU-VP-12/1;
and (ii) shortening of the antebrachium, which
retains primitive proportions in both specimens
(76). Drawings ©I.. Gudz.
wvvw.sciencemag.org SCIENCE VOL 284 23 APRIL 1999 6 3 3

R E P O R T S
Fig. 5, (A) A cladogram
depicting relationships
among widely recog-
nized early hominid
taxa, including the
new species A. garhi.
Note that an addition-
al clade is required
vi/hen tVi-o contempo-
rary forms of early
Homo are recognized
A variety of possible
cladograms have been
generated from the
data available in the
hominid fossil record,
but none of these sat-
isfactorily resolve the
polychotomy illustrat-
ed here (7 7), This cla-
dogram adds A, garhi
to the unresolved node.
(B) The chronological
relationships of early
bominld taxa. Age is
given in Ma. (C t o F)
Altemative phytogenies
depicting possible rela-
tionships among early
hominid taxa. Note that
these altematives do not exhaust tbe possibiOties and tbat not
all are entirely consistent with the cladogram. It is not presently
possible to choose among tbese

altematives. . • . ,
hubilis) or two (//. habiiis and H. rudulfen-
sis) species. Most phylogenetic efforts have
placed A. africanus as the link hetween A,
afureiisis and early Homo. This hypothesis
has been widely, hul not universally, ac-
cepted. Most predicted that a population of
A, africanus would be found in eastern
Africa when the 2.5 Ma gap there was filled
by fossil discoveries.
The 2.5 Ma A. garhi is derived toward me-
gadontia from A. afarensis, but in cranial anat-
omy it is definitively not A, africanus. Neither is
it a repre.sentative ofthe contemporary A, ae-
ihiopicus. It is in the right plaee. at the right
time, to he the ancestor of early Homo, however
defined. Nothing about its morphology would
preclude it from occupying this position. The
close spatial and temporal association between
.-i. ^arlii and behaviors thought to characterize
later Homo provide additional circumstantial
support. The temporal and possible phyloge-
netic placements of various hominid taxa rela-
tive to the new speeies from Bouri are reviewed
in Pig. 5.
Plio-Pleistocene hominid phylogenetics is
hcdeviled hy atomization of functionally coiTe-
lated character complexes that probably ema-
nate from restricted genomic shifts as well as
inadequate fossil samples (particularly for early
Homo). Table 1 compiles characters available
for A, garhi and related laxa hearing on phylo-
genetic placement. The discovery ofthe KNM-

DOI 10.1126science.1184944, 195 (2010);328 Science et .docx

DOI 10.1126science.1184944, 195 (2010);328 Science et .docx

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DOI 10.1126science.1184944, 195 (2010);328 Science et .docx