A RECONSIDERATION OF THE OMO KIBISH REMAINS

AND THE ERECTUS-SAPIENS TRANSITION

par

Michael H. DAY and Chris B. STRINGER

Abstract : The Omo-Kibish remains have been restudied in

the light of new finds including those from Arago.

The dating of the Kibish remains is reviewed and a

new reconstruction of Omo 1 is presented.

The affinities of the Omo-Kibish crania have

been reassessed making use of the newer principles

of classification that have emerged in the last ten

years. Working definitions of Homo erectus and Homo

sapiens are offered, based on distinctive within

group characters that can be identified objectively.

These definitions are employed to assess the affini-

ties of the Omo 1 and 2 crania in terms of a scoring

system.

The conclusion reached is that the Omo 1 cranium

can .be clearly aligned with anatomically modern Rome

sapiens while Omo 2 is closer to Homo erectus than to

the Neanderthals or to anatomically modern Homo sapiens

on the characters considered.

The dating of the two specimens remains a problem

in terms of absolute age and contemporaneity.

Comparison with Arago 21 shows that Omo 2 has

more in common with this specimen than Omo 1, although

Arago 21 and Omo 2 do not appear to be closely related.

Their similarities are mainly symplesiomorphies retained

from earlier Middle Pleistocene ancestors rather than

synamorphies.

St. Thomas's Hospital Medical Scholl - Lambeth Palace Road -London SEl 7EH, Grande-Bretagne.

6600-3000 B.P.

9500-7500 B.F.

>35,000 B.P.

— I I — it — +,1)-1 — ": , ( r `.1 1 I

1,11-M4 '1CP _

" -I p L.

IVb. Sands, tuff, silts. Bm

I Va. Clays, silts, sands, gravels. 13 .5 m

Soulzone — — — — Soil zone Ill. Clays, silts, sands, Shell bed with tuff and

zone shell beds. 46m

H. Silts with basal tuff. 22m

Tuff — - Soil zone

I — I I t I t i- t - 5 -I -

- "-I 5 1 1 , 5 1 — Hominid level • Tuff with

130,000 B.P. -7 s oil zone — oppP

Fig. 1.- Generalized stratigraphic column of the Kibish formation (courtesy ]Jr. K.W. Butzer).

I. Clays, silts, sands, gravels. +31m

TRACKS 4, C1 4 SITES

N1b.IV Kibish Formation

Mb.i Mb,I

Nhalabong Formation 0 500 '=r=neel

0SHIANGORO IVILLAGE

KENYA CAMP

STUDY AREA

ETI-HOPIA

SUDAN lano

Lake Stefanie

KENYA Loke Rudolf

The only archaeological evidence is a few stone tools

found with Omo I and they are undiagnostic of a re-

cognised culture.

The Omo 2 calvaria which was discovered approxi-

mately 2.5 km from the site of Omo 1 ("Fig. 2) is less

certainly dated since it was essentially a surface

find with no clear stratigraphic, faunal or cultural

context although the sedimentary sequence is reported

to be the same on both sides of the Omo river in this

area.

The Omo 3 fragments are thought to come from

Member III of the Kibish formation and are thus

slightly higher in the sequence, but still older than

37,000 years b.p. according to radiocarbon determina-

tions on molluscs from Member III (Butter, 1976).

Some of the initial conclusions concerning the

dating of the Omo material remain essentially un-

changed in that:-

a) Omo 1 is most clearly asasociated with

Member T in that it was/partly in situ

find that was properly excavated.

b) The contemporaneity of Omo 1 and the

associated faunal remains seems secure.

c) The uncertainty concerning the precise

stratigraphic level of the Omo 2 remains

leaves some doubt as to its contempor-

aneity with Omo 1. Omo 3 certainly

appears to be younger than Omo 1.

d) The chronological date of 130,000 years

b.p. for Member I by the Uranium/Thorium

method remains unconfirmed by any other

technique, but it is not contradicted by

the limited available faunal and radio

carbon dating,

010

Since the initial excavation, the site has not

been revisited and no further evidence as to its

dating has been published.

In terms of dating, therefore, several questions

can be posed. Is the relative dating evidence strong

enough to demand that the material be treated as a

single population sample? If the answer is yes, re-

construction and morphological, analysis can operate

within the bounds of variability of a local popula-

tion of a single taxon. If the answer is no, then

additional considerations arise in that the remains

may represent samples of time - successive populations

that are closely related to each other or they may

represent evidence of population replacement rather

than local in situ evolution.

• a. Previous work on the Omo-Kibish remains

The initial work on these remains included their

cleaning, restoration and description. The initial

assessment of the remains was based on anatomical

evidence and concluded that while all three specimens

should be attributed to Homo sapiens, specimens 1 and

2 show striking differences in skull form. The more

complete calvaria having features in common with the

Solo skulls, the Broken Hill skull and with Homo

erectus (Day, 1969). Later work including a discrim-

inant function analysis of metrical skull data

emphasised the differences between Omo 1 and Omo 2

and that both could be distinguished from at least

three populations of modern Homo sapiens (pay, 1973).

The Omo specimens were regarded as Neaderthals

(in the grade sense) by Brose & Wolpoff C1971), who

stated that no features of the specimens were outside

the range of Neanderthal morphology. Omo I "would

be identified as anatomically modern if found in

another context", but at the same time they made the

remarkable claim that the specimen was "extremely

similar to Amud". Overall, the Omo crania were

said to be Neanderthals (Sensu late), transitional

to "modern" H. sapiens, Howells (1974) strongly

disagreed with Brose & Wolpoff's (1971) general

approach and specifically criticised their conclu-

sions about the Omo specimens. We fully endorse

his criticisms.

Rightmire (Rightmire 1976; 1980; 1981)

favoured treating the specimens together as related

forms, while admitting that Omo 2 was more like

Broken Hill 1. As we also believe, Rightmire 01981)

felt that the unpublished Guomde specimen (KIN-ER

3884) from East Turkana might be related to the

Omo-Kibish fossils.

Stringer utilised multivariate analysis of

cranial measurements (1974) and analyses of size,

shape, angles and indices (1978) to compare the

Omo-Kibish specimens. The results tended to accen-

tuate the contrasts between the Omo crania, always

aligning Omo 1 much more closely to anatomically

modern (a.m.) H. sapiens. The multivariate analy-

ses (Stringer, 1974) were based on measurements of

Omo 2, and Omo 1 as reconstructed in.1972...,,.However

the new reconstruction presented here is only

marginally different in frontal dimensions and

cranial length from that of 1972, while parietal

and occipital regions have been retained. Thus the

1974 multivariate results comparing Omo 1 and 2 are

still relevant to the present discussion. The

analysis which employed most measurements for the

two specimens together utilised the following 13

measurements.

Biasterionic breadth (ASB); nasion-bregma chord,

subtense and fraction (FRC, FRS, FRF); bregma-

lambda chord, subtense and fraction (PAC, PAS,

PAF); lambda-opisthion subtense and fraction

(OCC, OCS, OCF); supraorbttal projection (SOS-

estimated for Omo 2); bistephanic breadth (STB);

maximum cranial breadth (XCB).

Discrimination between the groups analysed

was measured using the Mahalanobis D2

statistic,

and an extract from the results is provided below:-

2 D distance: etween Omo crania and other hominid

crania

Omo 1 Omo 2 Choukoutien 49.1 42.8

Solo 32.2 18,3

Neanderthal 35.8 40.5

Skhial 5 14.6 43.9

Upper Palaeolithic 18.6 48.1

Nearest modern (Norse) 16.1 46.1

Broken Hill 38.7 28.4' Irhoud 1 51.5 41.1

Singa 27.5 49.1

Petralona 59.5 60.5

Omo 1 24.3

Omo 2 24.3

Saccopastore 33.6 13.2

One 1 has nearest neighbours Skhal 5, the

Upper Palaeolithic group and a.m. Norse (all, in

our opinion, representative of a.m. Y. sapiens);

Omo 2 has nearest neighbours Saccopastore 1, Solo,

Omo 1, and Broken Hill. Of all the "non-modern"

specimens, Omo 2 is closest to Omo 1. Shared

differences from other archaic crania are the low

SOS, large FRC, large PAC, large PAF, large OCC.

.7"

Omo 2 calvaria

Shared differences compared with a.m. H. sapiens crania include larger XCB, STB, ASB, FRC, FRF and

PAF. Differences between Omo 1 and 2 mainly re-

late to contrasts in FRS (Omo 1 higher value -

more domed frontal), PAS (Omo 1 higher value -

more domed parietal), OCS (Omo 2 higher value -

more projecting occiput), OCF (Omo 1 higher value

- expanded occipital plane) and ASB (Omo 2 higher

value - broader occipital base), and in every one

of these differences Omo 1 is closer to the pattern

of a.m. H. sapiens crania.

Thus the multivariate results confirmed that

Omo 1 approximated to an anatomically modern

pattern in these cranial measurements, while Omo

2 did not. The two crania do share, however,

certain cranial characteristics suggesting that

they are related, though temporally separated,

members of an evolutionary lineage in north-east

Africa leading from erectus-like hominids to a

robust, but anatomically modern form. Alterna-

tively, if we accept the published dating, the .

Omo 1 cranium could represent a late Middle

Pleistocene/Upper Pleistocene spread of a.m.

R. sapiens into the area accompanied by some

degree of gene flow from a more archaic local

population represented by Omo 2.

Clark Howell (1978) was sceptical of the

Middle Pleistocene age estimates for the Omo-

Kibish crania, and questioned Day's (1973) con-

clusions regarding their affinities. He emphasized

their distinctiveness from R. erectus and H.

sapiens rhodesienses and concluded that they repre-

sented a late subspecies of H. sapiens closely

related to modern man. He quoted Stringer's (1974)

conclusions in support of this view, but these

results do not justify Howell's interpretation,

since Omo 2 is not closely related to recent H.

sapiens but is similar to various archaic specimens.

Fig. 4.— Superior view of Omo 2 (norms verticalis).

3. The Reconstruction of the Omo I cranium

The problems of the Kibish remains can also be

approached from the viewpoint of anatomical recon-

struction, governed by the internal evidence of

anatomical necessity rather than reconstruction by

the amalgamation of several species (vide Arago).

The reconstruction of undistorted cranial frag-

ments can proceed with confidence only if the frag-

ments concerned are adjacent and capable of a demon-

strable interlocking fit. Once those pieces that

have such a fit are identified and joined other

factors such as bilateral symmetry of skulls can aid

reasonable reconstruction.

In the case of the Omo 2 calvaria (Figs. 3 & 4)

the four fragments fit perfectly and the specimen is

undistorted. Any attempt to reconstruct the face

would be purely speculative and of little or -no

scientific value. Similarly with Omo 3 the paucity

of fragments (one left fronto-parietal fragment and

a glabellar fragment) does not allow any reasonable

attempt at reconstruction to be made. It is the

purpose of this paper to publish a reconstruction of

Omo 1 and to discuss the problems encountered and to

compare the Omo I reconstruction with the other Omo

(Kibish) remains and with other specimens to compar-

able age from Africa and from Europe. This, in turn,

may throw some light on the problems of the ex,eetus -

sapiens transition and contribute to the current

debate on punctuated equilibrium as opposed to gradu-

alism in this period of human evolution.

Omo 1 has a posterior vault which can be recon-

structed with some confidence, giving a decidedly .

"modern" appearance. To what extent should the re-

construction of the anterior region reflect this?

We believe the robust but anatomically modern morpho-

logy of the posterior vault should be mirrored by an

appropriate reconstruction of the frontal, face and

mandible. Using early anatomically modern specimens

Fig. 5.- Omo 1 reconstruction - frontal view (normal frontalis).

from S.W. Asia (Skinal, Qafzeh) and more archaic specimens from Africa (Irhoud 1, Ngaloba L.H.18, Broken Hill

1) it is possible to reconstruct a face which is

"modern" but which nevertheless reflects the robust

morphology of other late Middlejearly Upper Pleisto-

cene hominids by displaying a wide upper face, large

interorbital breadth and strong alveolar prognathism

(Fig. 5).

The frontal bone is very long, but some flexi-

bility is possible in the degree of flatness chosen

for the reconstruction (Fig. 6). The mandible has a

fairly narrow ascending ramus which would normally

indicate a short body and overall length. However,

given the constraints of the long frontal bone and

our preference for a face with some degree of alve-

olar prognathism, rather than an .orthognathic face,

the mandible has been reconstructed with a long body,

while avoiding the presence of retromolar spaces, not

otherwise found in African Pleistocene hominids.

4. New analyses and the classification of the Omo-

Kibish remains

Since the original studies of the Omo fossils,

much new material has been discovered and described

which is relevant to our interpretation of these

specimens. The characteristics of African H. erectus

are now better known, thanks to recent discoveries

and descriptions (Rightmire, 1980), while material

which throws light on the possible transition from

H. erectus and H. sapiens has been described from

sites such as Petralona, Arago and Bilzingsleben in

Europe (see e.g. Stringer et aZ., 1979) and Ndutu and

Bodo in Africa (Rightmire, 1980; 1981). Archaic

hominid material from Broken Hill and possible early

anatomically modern material from Florisbad may be

more ancient than had been supposed, probably dating

lEi lEI 1E1 1 1

I

Fig. 6.- Omo 1 reconstruction - superior view (norma verticalis).

from the Middle Pleistocene and early Upper Pleis-

tocene respectively (Rightmire, 1981), while other

African material which may document the latter

stages of hominid evolution has been described from

sites such as Djebel Trhoud (Howell, 1978) and Ngaloba (Day et al., 1980), From Border Cave and Klasies

Cave in Southern Africa, material which may represent

anatomically modern hominids from the early Upper

Pleistocene has been described CRightmire, 1981).

From all this additional knowledge we should now

be in a better position to assess the affinities of

the Omo-Kibish crania than was possible ten years ago,

but the intervening years have also seen reassessments

of the principles to be used in classifying fossil

hominids and a growing recognition of the problems we

face in interpreting a fragmented fossil record with

poor chronological control, against a background of

debate about the fundamental mechanisms of evolution-

ary change. Following some common palaeoanthropologi-

cal methods of classification we might use the "total

morphological pattern" approach of Le Gros Clark

(1964) or employ a multivariate approach (e.g. Stringer,

1974) to produce measures of overall similarity between

fossil hominids and recent populations. But such

approaches are primarily phenetic, often leading to the

creation of grade systems, disguised by the use of

subspecies names (Campbell, 1964; Howell, 1978) or

overt in the application of numbered grades (Stringer,

et al., 1979). When one of us suggested a grade system

for H. sapiens, it was because it was felt that the

application of subspecies names to fossils was hinder-

ing rather than helping the progress of palaeoanthro-

pology.

A numbered grade system should only be employed

pending the creation of valid taxonomic units, and

could not be a workable solution in the long term.

As a first step towards a different approach to

hominid classification we would like to propose

simple working definitions of H. erectus and H.

sapiens based on distinctive within-group character-

istics which can be used to assess the affinities of

the Omo-Kibish fossils. Most of the characters have

previously been used in describing the two species

but we have attempted to provide clear i presence or

absence data which can be assessed objectively and

applied simply. Some of the metrical differences

recognised can be shown to lie behind multivariate

discrimination (see Stringer, 1974; 1978 and earlier

discussion of the Omo multivariate results), although

this is sometimes masked by amalgamation of size and

shape differences. Once broad groupings CH. erectus,

Neanderthals and a.m. H. sapiens) are established, it

should be possible to recognise further subdivisions

and identify other groupings for fossils which do not

fit well into any of these categories. More detailed

definitions based on more anatomical characters,

including those most generally used (e.g. see Le Gros

Clark, 1964; Howell, 1978;Howells„1980) would be de-

sirable, but without clear character weighting it is

difficult to classify fossil hominids which show only

some of these features, or which have characters only

partly developed.

It seems appropriate to begin with a definition

of a.m. E. sapiens based on derived characters which

can be assessed in the Omo specimens. There is a

large body of data available (Howells, 1973). Indeed

if we cannot provide a valid definition of the only

living human species there is little hope of our re-

cognising extinct taxa. Whether the species so recog-

nised should also form the basis for recognising the

species in the fossil record is a difficult problem,

but it does seem somewhat inappropriate to include in

the species fossil hominids which lack most of the

derived characters defining H. sapiens today. But

for the present we will equate our definition of H. sapiens (Sensu stricto) with the term a.m. H. sapiens,

and leave the question of whether various archaic

forms rightly belong within the species H. sapiens

to future research. The criteria used here to de-

fine a.m. H. sapiens will not all be present in all

modern specimens, but a majority should always be

present. Because of population variability, some

of these characters will also be found in fossil

hominids which are clearly not anatomically modern

forms. But if either of the Omo-Kibish specimens

can reasonably be classified as a.m. H. sapiens, we

should expect over 50% of the "modern" characters

to be present of those which can be tested.

Working definition of anatomically modern H. sapiens:

- Cranium short but high (ratio of basion-bregma

height or vertex radius to glabello-occipital length

should exceed 0.70 or 0.64 respectively);

Parietal arch is long and high, inferiorly

narrow, superiorly broad (parietal angle less than

1380, ratio of bregma-asterion chord to biasterionic

breadth greater than 1.19);

- Frontal bone high (frontal angle less than 133°);

- Supraorbital torus not continuous, but divided

into lateral and medial portions;

- Occipital bone well curved rather than angulated

(occipital angle more than 114°);

- Mental eminence on mandible;

- Gracile limb bones - thin walled with relatively

small articular surfaces.

For Homo erectus

Fossil material from Africa and Asia can simi-

larly be used to produce a working definition of H.

erectus. Material used here to formulate the mor-

phological and metrical definition includes KNM-ER

3733 and 3883; Choukoutien; Sangiran 2,4,17; and

Ngandong. The characters chosen exclude some of

the useful traditional characters (e.g. thick occi-

pital torus, presence of angular torus, presence of

mid-sagittal keeling and parasagittal depressions)

because these cannot be defined precisely or object-

ively. Such characters should also be assessed in

any overall study of the Omo-Kibish material and

have previously been investigated (e.g. Day, 1969;

1971). The characters chosen for Table 1 will all

be present in some H. eretus crania, and the majority should be present in all H. erectus crania. Other fossils will display some H. erectus characters even though they are not members of the species R. erectus, since our working definition is primarily created to separate H. erectus most effectively from anatomically modern H. sapiens. Other characters would

have to be utilised if we were trying to separate

Neanderthals from H. erectus, since they share some

of the characters which reflect the presence of a

long, low skull, low frontal and short flat parietal

arch, and this will have to be investigated in the

future. But Neanderthal crania do not show a

majority of the H. erectus characters, and a set of criteria differentiating Neanderthals from a.m. H. sapiens can also be created to test whether either

of the Omo-Kibish crania could be regarded as

"Neanderthal" gable 3). If specimens are found

that display combinations of characters typical of

the various groups (or intermediate values for cer-tain characters) this may indicate a) that they

represent genuine morphological intermediates between,

the forms, b) that they are hybrids if it can be

demonstrated that the morphologically distinct groups

overlap in time, or c) that the characters used in

the working definitions are inadequate and need

modification.

Working definition of 11. erectus:

- Cranium long and low (ratio of basion-bregma

height or vertex radius height to glabello-occipital

length is less than 0.62 or 0.58 respectively);

- Inion is coincident with opisthocranion;

- Thick cranial walls (for example parietal thick-

ness at bregma exceeds 8 mm, at asterion exceeds

14 mm, on occipital at inion exceeds 14 mm);

- Angulated occipital bone (occipital angle less

than 107°);

- Expanded nuchal portion of occipital bone

Cinion-opisthion chord exceeds lambda-inion chord);

- Inion more than 25 mm above internal occipital

protuberance);

- Parietal arch flat, short and low, superiorly

narrow, inferiorly broad (parietal angle exceeds

145.5°, ratio of bregma-asterion chord to biasterionic

breadth is less than 1.14);

Low frontal bone (frontal angle exceeds 136.5°);

- Cranial capacity generally below 1150 ml.

5. Conclusions: the affinities of the Omo-Kibish

fossils

In Tables 1,2 and 3 it is evident from the

characters considered that Omo 1 and 2 differ mark-

edly in their affinities, far more than would be

expected for one population. Omo 2 shows most resem-

blance to H. erectus, the main differences being related to larger cranial capacity and associated

vertical expansion of the cranial vault reflected by

a large vertex radius and bregma-asterion chord.

The occipital bone shows various typical erectus characters but it is actually less angulated than the

majority of other erectus crania. Omo 1 is clearly aligned with a.m. H. sapiens although the low and long

frontal bone of the reconstructed cranium is exceptional

and the robusticity of the specimen is indicated by

relatively thick cranial walls. It would be premature

to assign the Omo 2 fossil to the species H. erectus when some important anatomical areas are not represented

Ce.g. face, dentition, mandible, post-cranium) and there

are clear departures in supraorbital torus morphology,

cranial capacity and overall dimensions from the typical

and fairly consistent sample of H. erectus crania from

Africa and Asia. However the affinities of the specimen

are certainly closer to H. erectus than to the Neander-

thals or a.m. H. sapiens on the characters assessed here.

For Omo 1 we feel we have sufficient evidence from the

cranial parts, mandible and post-cranium to align the

specimen positively with a.m. H. sapiens, despite its

robusticity.

The main problems remaining are chronological. If

both specimens are of late Middle/early Upper Pleisto-.

cene age, then two distinct but approximately contem-

poraneous populations are being sampled. One of them

conformed to an anatomically modern pattern and would

represent one of the most ancient if not the most

ancient of such groups known. But a note of caution

must be injected at this point. Further confirmatory

absolute dating analyses have not been performed,

neither has subsequent field work been conducted in the

area to recover further material, including faunal re-

mains which might be more diagnostic of a Middle or

Upper Pleistocene age. Given the evidence from South-

ern Africa (Rightmire, 1981) it is no longer implausible

that anatomically modern hominids existed at the

beginning of the Upper Pleistocene. What would be

difficult to explain however is the occurrence of

such widely separated early anatomically modern

hominids when more archaic populations may still

have existed in North Africa and in the intervening

area of East Africa. Perhaps the dating of hominids

in East Africa such as Eyasi, Broken Hill and

Ngaloba may be significantly earlier than the more

"modern" specimens, or there may have been a rapid

population replacement in the early Upper Pleisto-

cene. However this cannot be demonstrated within

our present inadequate dating framework.

Alternatively the evolution of hominids resem-

bling anatomically modern man may have occurred more

or less independently in areas of Southern, Eastern

and Northern Africa, in which case the Omo-Kibish

remains may document a transition from an ercctus-like Cnot Neanderthal) ancestor to a robust but,

"modern" skeletal form. Whichever model eventually

proves most appropriate it is evident that relation-

ships between the contrasting Omo-Kibish specimens

will remain somewhat problematical until further

evidence is available about their relative chrono-

logical positions.

6. The Omo remains and the Arago 21 construction

One of the purposes of this symposium is to

discuss the new reconstruction of the Arago 21

specimen, and through comparative analyses, to place

the specimen in relation to various other fossil

hominids. Our reconstruction of the Gmo 1 cranium

was made 'using the available fragments, directly

where possible, or indirectly as indicators of the

probable morphology of missing parts. We did not use fragments of other fossil hominids in our re-

construction, but rather attempted to'produce a

reasonable reconstruction given the available frag-

ments and the morphology of other late Middlelearly

Upper Pleistocene crania. For the Arago reconstruc-

tion, modified parts of other fossils have been used

to create a composite cranium containing fragments

from specimens such as Sangiran 17, Swanscombe or

Vertesszbllbs to represent the missing parts of the

skull.

Direct comparisons between the Arago cranium

and the Omo fossils are difficult since the former

specimen consists primarily of parts not well repre-

sented in the latter (upper dentition, palate, face,

supraorbital region), and some of the most informa-

tive parts of the Omo crania (mastoid region occipital

bone, mandible and postcranium of Omo 1) are not

present in the Arago 21 cranium itself. Comparisons

can be made for the frontal bone and parietal region

and except for the common feature of a long and flat

frontal bone (accepting the Omo 1 reconstruction),

there are immediate contrasts between the specimens.

The Arago frontal certainly appears more archaic in

its massive supraorbital torus and narrow dimensions,

with a significant degree of postorbital constriction.

The latter character is no doubt related to the lower

cranial capacity of the Arago specimen.

In parietal morphology there are also contrasts

since Omo 1 displays a much more modern form than

Arago 47 (as reconstructed) while Omo 2 appears rather

archaic in comparison, with a midsagittal keel, para-

sagittal flattenings and a broad base to the parietal

arch. But some of the most important diagnostic

characters which separate the Omo crania are in the

occipital bone, which is unfortunately lacking in the

Arago specimen. Given the morphology of the face and

frontal bone, a more archaic occipital than that of

the Swanscombe specimen was probably present and there-

fore the VertesszbllUs, Petralona or Bilzingsleben

occipitals may be more appropriate models for the

Arago reconstruction. It is true that the Arago 47

parietal may appear rather "advanced" in certain

respects, but the arch has been reconstructed with

a low biasterionic breadth in comparison with all

other European Middle Pleistocene hominids except the

Steinheim cranium. In addition, the parietal form

of specimens such as Petralona, Biache, Steinheim and

Ehringsdorf 9 is very "progressive" in certain res-

pects, and this characteristic seems to be a signifi-

cant derived character for European Middle Pleisto-

cene hominids generally compared with H. erectus

fossils. It is not always matched by the morphology

of the occipital bone (vide Petralona). The strong

angular torus of the Arago 47 parietal compared with

the Petralona specimen may also be a clue to the

robusticity to be expected in the occipital bone.

Thus the Arago occipital bone would probably have

been much more archaic than that of Omo 1, perhaps

resembling that of Omo 2 more closely. The temporal

bone of European Middle Pleistocene hominids (such as

Petralona, Steinheim and perhaps Ehringsdorf 9) also

shows distinctive, more modern characters compared

with those of Asian H. erectus fossils, and therefore

the Arago temporal bones may have resembled those of

European hominids (or Broken Hill 1) rather than

Sangiran 17.

As we have already discussed, we believe that

Omo 1 must be classified as an a.m. H. sapiens, For

Omo 2 and Arago 21, the choice is not so easy. Under

the generally accepted system for hominid classifica-

tion, the choice of taxon would lie between H. erectus

and some form of "archaic" H. sapiens. In differen-

tiating between E. erectus and H. sapiens (sensu Zeta)

the ultimate classification depends entirely on which

characters are considered most significant. If endo-

cranial volume and supraorbital torus morphology are

considered important, Arago 21 would probably be

classified as H. erectus and Omo 2 as H. sapiens.

If occipital morphology is emphasised, Omo 2 would

probably be classified as H. erectus while Arago 21

could not even be assessed. In details of parietal

form, the two specimens show different combinations of erectus-like and sapiens-like characters, but

share a flat parietal bone, typical of erectus,

with a parietal arch which is "advanced" in being

higher, diagonally longer and (as reconstructed for

Arago) relatively narrow inferiorly. If we define

H. erectus only by the shared derived characters of

the Asian and early African specimens then Arago 21

and Omo 2 both show significant, but distinct de-

partures from this condition. If however we adopt

a broader definition of H. erectus to include fossils

often regarded as "archaic" H. sapiens (e.g. Broken

Hill, Petralona) then both could be included in such

a group. Yet another alternative is to recognise a

third group for such specimens which display mosaic

or intermediate characters. We have both suggested

names for such a group in the past. Day (1973) pro-

posed that they be regarded as a "Pithecanthropoid

Intermediate" group, while Stringer et ai.,C1979)

suggested the term "H. sapiens grade I". Either of

these terms are still preferred by us to the alloca-

tion of sub-specific names which are of dubious

applicability and usefulness.

Eventually it may be possible to recognise sub-

sets within this grouping of "intermediate" fossils

based on derived characters probably linking the

Arago fossils with other European Middle Pleistocene

specimens, and perhaps ultimately, with the Neander-

thals. But convincing synapomorphies with the

Neanderthals are difficult to detect in the European

hominids until'the later Middle Pleistocene and the

search for derived characters linking together the

African fossils of this time is an even more diffi-

cult task. Ultimately the Arago and Omo 2 fossils

will probably not be classified together except in a

generalised grade framework. They do not appear to

be closely related specimens and their grade similar-

ities rest mainly on symplesiomorphies retained

from, earlier Middle Pleistocene ancestors rather than

on synapomorphies. But we are unable to propose a

definitive classification at the moment beyond suggest-

ing that neither belong in H. erectus sensu stricto

or H. sapiens sensu strict°.

REFERENCES

Brose, D.S. & Wolpoff, M.H. 1971. Early Upper Paleo-

lithic man and late Middle Paleolithic tools. American Anthropologist 73: 1156-1194.

Butzer, K.W. 1969. Geological Interpretation of Two Pleistocene Hominid ,Sites in the Lower Omo

Basin. Nature 222: 1133-1135.

Butzer, K.W. 1976. The Mursi, Nkalabong and Kibish

Formations, Lower Omo Basin, Ethiopia. In

Earliest Man and Environments in the Lake Rudolf

Basin Edited: Y. Coppens, F.C. Howell, G.L1.

Isaac & R.E.F. Leakey. Chicago: University of

Chicago Press. Pp. 12-23.

Butzer, K.W. & Thurber, D.L. 1969. Some Late Cenozoic

Sedimentary Formations of the Lower Omo Basin.

Nature 222: 1138-1143.

Butzer, K.W., Brown, F.H. & Thurber, D.L. 1969. Hori-

zontal sediments of the Lower Omo Valley: the

Kibish Formation. Quaternaria 11: 15-29.

Campbell, B.G. 1964. Quantitative taxonomy and human

evolution. In Classification and Human Evolution.

Edited: S.L. Washburn. Chicago: Aldine. Pp. 50-74.

Day, M.H. 1969. Omo Human Skeletal Remains. Nature 222: 1135-1138.

Day, M.H. 1972. The Omo human skeletal remains. In The origin of Homo sapiens. Edited: F. Bordes.

Paris: Unesco. Pp. 31-35.

Day, M.H. 1973. The Development of Homo sapiens. In

L'origine Dell 'Homo. (Darwin Centenary Symposium

on the origin of man). Roma: Accademia Nazionale

Del Lincei. Pp. 87-95.

Day, M.H., Leakey, M.D. & Magori, C. 1980. A new fossil

hominid skull CL.H.18) from the Ngaloba• Beds,

Laetoli, Northern Tanzania. Nature 284: 55-56

Howell, F.C. 1978. Hominidae. In Evolution of African

Mammals. Edited: V.J. Maglio & H.B.S. Cooke.

Cambridge: Harvard University Press. Pp. 154-248.

Howells, W.W. 1973. Cranial variation in Ban: a study

by multivariate analysis of patterns of difference

among recent human populations. Papers of the Pea-

body Museum. 67: 1-259 (whole volume).

P

Howells, W.W. 1974. Neanderthals: Names, Hypotheses and

Scientific Method. American Anthropologist 76: 24-38.

Howells, W.W. 1980. Homo erectus - Who When and Where: A

Survey. Yearbook of Physical Anthropology 23: 1-23.

Leakey, R.E.F. 1969. Early Homo sapiens remains from the

Omo River region of south-west Ethiopia: Faunal

Remains from the Omo Valley Nature 222: 1132-1133.

Le Gros Clark, W.E. 1964. The fossil evidence for Human

evidence. Chicago: University of Chicago Press.

Rightmire, G.P. 1976. Relationships of Middle and Upper

Pleistocene hominids from sub-Saharan Africa.

Nature 260: 238-240.

Rightmire, G.P. 1980. Homo erectus and human evolution

in the African Middle Pleistocene. In Current

Argument on Early Man. Edited: L.-K. Konigsson.

Oxford: Pergamon. Pp. 70-85.

ightmire, G.P. 1981. Later Pleistocene hominids of

eastern and southern Africa. Anthropologic Brno.

19: 15-26.

Stringer, C.B. 1974. Population relationships of later

Pleistocene hominids: a multivariate study of

available crania. Journal of Archaeological Science .

1: 317-342.

Stringer, C.B. 1978. Some problems in Middle and Upper

Pleistocene hominid relationships. In Recent

advances in Primatology. Vol. 3. Evolution.

Edited: D.J. Chivers & K.A. Joysey. London: Academic

Press. Pp. 395-418.

Stringer, C.B., Howell, F.C. & Melentis, J.K. 1979. The

Significance of the Fossil Hominid Skull from

Petralona, Greece. Journal of Archaeological Science

6: 235-253.

Stringer, C.B. & Trinkaus, E. 1981. The Shandar Neanderthal

Crania. In Aspects of Human Evolution. Edited: C.B.

Stringer. London: Taylor & Francis. Pp. 129-165.

TABLES 1 & 2:

and anatomi-

Lk a) O

a) a)

Ca •P U U

f-F O

F~ u al 0

Ca

• g aS a)

Ca to

.r1 0) 4 hD U O - .0 0 X 1:3 0. to iK 0 a

tr)

- 60 g

) to

0 a Ca

• • H

C) Ca 0) a) a)

F, _Ca In • -P

g.

cally modern H.

•

4- )

m

are expected to be

Characters

remains.

Cn 0

C)▪ .

same criteria.

Aa

a)

Fes-, La

Arago 21 reconstruction is also tested

erectus (characters

Ca 0

0)

1-1

O bn Ca

•c(

O a O

0

0

Ca 41

differentiate from a.m. H.

nIN

rl 'to O

Cd CO 0 tO.

I a) Z 0.3 1.f1

Ctl

ttdrrs

r•I Ca Cd g g

I bl) bly

cd id g

II. g " • . , n , ■ , 0

rH I •..0

03 Cd t'r)

g 0 , .1-1 v.-1 taD c-... to I:10 •

0 0 i•-■ 0 0 0 0 0 0 0 1-1 U 0 Z Z ca Z 7 Z Z Z Z cd '-' Z

a a

Thick cranium:

Inion = opisthocranion

VRR/GOL <0.58

0

Cranial capacity .11150 ml

BBH/GOL <0.62

tol. ,e-4■

4--I ctS cC

• g [o to 0 g

•

to to 0 u) 0 a) z a) 0 Z

bo • k

U Cd cC

0 a-J O -1- i-t ..--1

a p.0 • o - as cIS 4--, P. if) rI Ln 4-1 4-) 4,1 0 0 0) 4.1 04 E.-. r0 N at C%.1

Lf) r•-1 V '0

• .-1 ..-4 ,--i 0 I u A 4 , ..i- gal to

Cdk k u -.-1 .1-4 1--1 Cr) r-I ctl IS V Ca Ca 0 S=1., A < A

0-. P.. 0 0 0 .ri -..... < .1-i. •r-t .,-1 u ..t

,^-, ,-, U g 0 0 U < < g '-cd".6 4:1 U 0 I-I .."1 [-I 0 04 P:1 f.11

above internal

cm e—, N. to') 00 0

O

r--

0 Z

co v, c, z z

>-■

Mental eminence

weakly developed lateral and

Clearly divided suptaorbital

CO 1.1 d ul

U) Vi Ul

ca.

CO 0 a) a) 0 0

Ct$ 0 rl

0 0 131) F-4 cd

0 0 z

I Ln.

wN

0 0 -.1" ai

•

V% .1% 1-4 0C.O.

0 CD

$2:1 1:4

° cO

ri V

‹, 1;41

n 0

rs ‹G' v

1,1 13:1 s

mall articular surfaces

Limb bones thin-walled with relatively

Arago 21 recon.

O E 0

0

0

td • 'tj A

• '71

E. sapiens (characters of modern

to differentiate from H.

erectus

Neanderthals)).

Arago 21 recon.

The Arago 21 reconstruction is also tested.

described as "Neanderthal" rather than as related

Selected metrical and morphological characters whish distinguish between

(Stringer & Trinkaus,

Relevant Neanderthal characters

to H. erectus or a.m. H.

Neanderthal and a.m.

either Omo

9) Limb bones thick walled with relatively

O z

large articular

ao

00

* Several of the more diagnostic Neanderthal characters of the face and post-cranium

cannot be used because of the incomplete nature of the Omo-Kibish finds. The Arago

21 specimendoes not show these' most distinctive Neanderthal characters of the face

~fi 01

D

ca

R

t3

0)

and hence would

classified as a Neanderthal using all available criteria.

-g I-, 4-, • •r-1 cd

4 r.) - H

cd

• ri ri

-H • cd

ra) xy

'717,71,71.1T, Le)

4) a) Ca cd

Anterior mastoid

erectus.

Cranial shape

Nasio-frontal angle

Large occipitomastoid crest

Suprainiac fossa

VI V/ 0 0 0 0 Z

cc! g 0 0 0 o o r

ZZZZ +DA

cd a)

'JD /7=1 cD

O H ri g 4-3

g rn u cc) cd cd cu 0 8

(1) P•

▪ tcr 0 0 0 0 O o O a)

er, er, rr, H) V 1-r) 00

L'HOMME DE PETRALONA :

COMPARAISONS AVEC L'HOMME DE TAUTAVEL

par

Louis de BONIS*et Jean MELENTIS"

}Mourne :

Malgre des differences, dont quelques unes sans doute liges an

sexe, le crane de Petralona et l'homme de Tautavel presentent plusieurs

points communs. Certains de ceux-ci correspondent A des caracteres que

l'on pent considerer come primitifs et gvoquent le stade archaique

d'Homo erectus. On peut relever la forme du torus sus-orbitaire, les

proportions du frontal, l'aplatissement du parietal ou la robustesse de

la denture. D'autres en revanche sont des synapomorphies, des caracteres

derives partages avec la sous-espece Homo sapiens neandertalensis ; ils

permettent de classer les deux fossiles dans cette sous-espece. Sur la

base des memos criteres on doit faire entret dans ce taxon les formes

africaines de Broken Hill et de Bodo. Un cladogramme resume cette hypo-

these phyletique et d'autres opinions sont discutges.

Cette ligngesemble s'etre developpee en Europe et avoir envahi

l'Afrique au morns A deux reprises. Wapres les datations effectuees A

Tautavel et A Petralona la divergence entre les deux sous-especes d'Homo

sapiens semble avoir ate tres precoce.

Abstract :

Petralona and Tautavel men show several differences, some of them

resulting from sexual differences. They show also a lot of similarities.

Some of these similarities are primitive or plesiomorphic characters shared

with the archaic man Homo erectus. They are the shape of the supraorbital

torus, the narrowness of the frontal bone, the flatnessof the parietal

bone and the robustness of the dentition. The other ones are synapomorphies

or derived characters shared with the sub-species Homo sapiens neandertalen-

sis. They are the shape of the maxillar without canine fosse, the low posi-

tion of the infra-orbital foramen, the shape of the malar bone and the

*Universite de Poitiers - Facultg des Sciences - Laboratoire de Paleontologie des Vertebras et de Paleontologie humaine -40 avenue du Recteur Pineau - 86022 Poitiers cedex.

"Universite de Thessalonique - Laboratoire de Geologie et Paleontologie - Thessalonique - Grace.