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Virtual Assessment of the Endocranial Morphology of the Early Modern European Fossil Calvaria From Cioclovina Romania.

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THE ANATOMICAL RECORD 294:1083–1092 (2011)
Virtual Assessment of the Endocranial
Morphology of the Early Modern
European Fossil Calvaria From
Cioclovina, Romania
ELENA F. KRANIOTI,1 RALPH HOLLOWAY,2 SASCHA SENCK,3 TUDOR CIPRUT,4
DAN GRIGORESCU,5 AND KATERINA HARVATI6*
1
Forensic Anthropology, School of History, Classics and Archaeology, University of
Edinburgh, Edinburgh, Scotland
2
Department of Anthropology, Columbia University, New York, New York
3
Department of Anthropology, University of Vienna, Vienna, Austria
4
Radiology Department, Centrul De Sanatate Pro-Life SRL, Bucharest, Romania
5
Department of Paleontology, University of Bucharest, Romania
6
Paleoanthropology, Department of Early Prehistory and Quaternary Ecology and
Senckenberg Center for Human Evolution and Paleoecology, Eberhard Karls Universität
Tübingen, Rümelinstrasse 23, Tübingen 72070, Germany
ABSTRACT
Endocasts provide evidence on size and shape characteristics, blood
supply trajectories, and neurological features of the brain, allowing comparative analyses of fossil hominins crucial to our understanding of
human brain evolution. Here, we assess the morphological features of the
virtual endocast of the Cioclovina Upper Paleolithic calvarium, one of the
earliest reliably dated European modern human fossils. Our study was
conducted on a computed tomography (CT) scan of the original specimen.
The endocranial profile was approximated via a semiautomatic segmentation of the CT data. Virtual reconstructions of the endocast were used for
assessing the morphological features of the endocranium and for the estimation of the endocranial volume. Cioclovina exhibits a clockwise torque
with a small anterior extension of the left frontal lobe over the right one
and a protrusion of the right occipital lobe over the left, most likely due
to the superior sagittal sinus coursing over the occipital pole. There is an
obvious right predominance of the posterior drainage system. Interestingly, the area of the frontal sinus is occupied by dense bony tissue with
small air cells corresponding probably to a natural bony loss in the diploë
and to vascular spaces. An estimated endocranial volume of 1498.53 cc
was calculated. The convolutional details of the third inferior frontal
gyrus (Broca’s caps) are indistinguishable from those found in modern
Homo sapiens, and the left occipital lobe appears wider than the right, a
possible correlate of right-handedness. Our metric analysis of endocranial
measurements also aligns Cioclovina with modern humans. Anat Rec,
C 2011 Wiley-Liss, Inc.
294:1083–1092, 2011. V
Grant sponsors: Marie Curie Research Training Network;
Grant number: MRTN-CT-019564; Institute for Aegean
Prehistory; Max Planck Society.
*Correspondence to: Dr. Katerina Harvati, Paleoanthropology,
Department of Early Prehistory and Quaternary Ecology and
Senckenberg Center for Human Evolution and Paleoecology,
Eberhard Karls Universität Tübingen, Rümelinstrasse 23,
Tübingen 72070, Germany. Fax: þ49-07071-29-5717.
E-mail: katerina.harvati@ifu.uni-tuebingen.de
C 2011 WILEY-LISS, INC.
V
Received 21 June 2010; Accepted 25 March 2011
DOI 10.1002/ar.21420
Published online 1 June 2011 in Wiley Online Library
(wileyonlinelibrary.com).
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KRANIOTI ET AL.
Key words: endocast; virtual reconstruction; modern human
origins
Cioclovina is one of the earliest reliably dated modern
human fossils found in Europe. It was discovered in
1941, during phosphate mining of the Pes
tera Cioclovina
cave, South Transylvania (Harvati et al., 2007) and constitutes a well-preserved calvarium (Fig. 1). The specimen is dated by recent direct AMS 14C to an age of
29,000þ–700 ka (Olariu et al., 2003) and 28,510þ–170
(ultrafiltration pretreatment; Soficaru et al., 2007) and
assigned to the Aurignacian (e.g., Churchill and Smith,
2000). It preserves the cranial vault and much of its cranial base, while the face is almost entirely absent: only
the frontal aspect of the orbits and the upper part of the
nasal bones are preserved. The cranium is in good condition and appears to have suffered minimal postmortem
distortion. The initial description by Rainer and Simionescu (1942) considered this specimen as a young
female. Later studies (Smith, 1984; Harvati et al., 2007;
Soficaru et al., 2007) are divided on this point. The overall morphology of the cranium is unquestionably modern
human (Rainer and Simionescu, 1942; Necrasov and
Cristescu, 1965; Harvati et al., 2007). Some authors
have suggested the possibility of partial Neanderthal
ancestry for Cioclovina based on their interpretation of
the nuchal region (Soficaru et al., 2007; Trinkaus, 2007).
According to this view, Cioclovina possesses a suprainiac
fossa reminiscent of, though not exactly the same as, the
Neanderthal condition often cited as a Neanderthal
autapomorphic feature (e.g., Santa Luca, 1978). This
interpretation has been disputed. Harvati et al. (2007)
applied several criteria developed from the literature to
recognize hybrids in the fossil record, including heterosis/dysgenesis, supernumerary teeth and extra sutures,
and intermediate shape. None of these criteria suggested
that Cioclovina might represent a hybrid. Harvati et al.
(2007) further consider the suprainiac morphology of the
specimen to lie within the normal range of modern
human variation in this anatomical region.
Here, we describe the endocranium of the Cioclovina
specimen, including the endocast, frontal sinus morphology, as well as the middle meningeal vessel and occipital
venous sinus imprints. Where possible, we identify gyri
and sulci, particularly on the prefrontal lobe. Some of
these traits have been shown to differ between modern
and fossil humans. We evaluate these anatomical features with special reference to Neanderthal and modern
human endocranial morphology.
MATERIALS AND METHODS
This study was conducted on a computed tomography
(CT) scan of the original Cioclovina calvaria. Scanning
was performed using a Siemens sensation 64 medical CT
scanner in the facilities of the Centrul De Sanatate ProLife SRL, Bucharest. The scanning direction was coronal
(transverse). Slice thickness of 0.625 mm, X-ray tube
voltage 120 kV and tube current 304 mA were used. All
slices were formatted in the same size of 512 512 pix-
els. The reconstruction diameter and pixel resolution
were 223 and 0.44 mm. The half-maximum height protocol (Spoor et al., 1993) was used to reconstruct each cranial surface from the CT scan via the software package
Amira (Mercury Computer Systems, Chelmsford, MA).
To obtain an approximation of the total endocranial
volume, missing parts of the cranial base were virtually
reconstructed by using a modern human cranium as reference. We determined the reference by carrying out a
generalized Procrustes analysis (GPA) and a subsequent
principal components analysis (PCA) in form space (Mitteroecker et al., 2004) on 34 anatomical landmarks present in 25 modern human crania and Cioclovina and
chose the specimen that was closest to the Upper Paleolithic calvarium in terms of Procrustes distance (Bookstein, 1991). The specimen closest to Cioclovina was a
20-year-old female of Southern African origin (VA24)
with an endocranial volume of 1365.43 cc.
The missing area incorporates the medial part of the
left cerebral fossa, the clivus, the anterior and posterior
clinoid processes, parts of the dorsum sellae, the ala
minor, the lamina cribrosa, and the posterior part of the
orbital roof formed by the frontal bone. Using the opensource software Edgewarp3D (Bookstein and Green,
2002) and AMIRA 5.3, a three-dimensional (3D)-template of 508 anatomical landmarks (n ¼ 34) and semilandmarks (n ¼ 474) was created to capture the
geometry of the complete endocranial surface of the reference. We estimate missing data using thin plate
splines (TPS; Bookstein, 1991) by warping the complete
reference cranium onto the target; in this case, the cranial remains of Cioclovina. This procedure aligns the reference and the target according to homologous
anatomical landmarks present in both models. First, a
TPS interpolation based on the anatomical landmarks
was computed to warp all semilandmarks from the reference to Cioclovina. In this way, the reference and target
are aligned according to the anatomical landmarks; and
all semilandmarks are roughly estimated according to
minimum bending energy of just the landmarks. In a following step, each semilandmark is projected onto the
preserved parts of the respective endocranial surface of
Cioclovina and slid along tangents to the surfaces. Landmarks on the reference that correspond to the missing
area in Cioclovina were manually declared as ‘‘fully
relaxed,’’ that is, missing, and are estimated according
to the TPS algorithm. Finally, the estimated subcranial
parts that are corresponding to the missing area in Cioclovina were fused with the original virtual endocast.
The virtual reconstruction (Fig. 2) was used for the
quantification of the total endocranial volume and for
visually assessing the morphological features of the
endocranium. The analysis, segmentation, and measurements were performed using Amira 5.3.
Cioclovina’s virtual endocast was aligned in dorsal
view, and markers were placed on the left (FR-L) and
right frontal pole (FR-R) and the left (OC-L) and right
CIOCLOVINA ENDOCRANIAL MORPHOLOGY
1085
Fig. 1. Top: Map of Romania showing the approximate location of the Cioclovina cave. Bottom: the
Cioclovina cranium in lateral view.
occipital pole (OC-R). In the right lateral view, the
markers were placed on the vertex (V) and most caudal
cerebellar pole (CP). These placements were checked
with dorsal and posterior views. The endocast was then
rotated to occipital view, and markers were added at the
most projecting points laterally on both hemispheres of
the cerebrum and at the most laterally projecting points
of the cerebellum (at the outside edges of the sigmoid
sinuses, if visible) and to the most laterally projected
points of the endocast. Additional markers for lambda
and bregma were placed with the endocast positioned in
occipital and dorsal view, respectively. A series of
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KRANIOTI ET AL.
Fig. 2. Virtual reconstruction of Cioclovina endocast: (A) frontal, (B) occipital, (C) right lateral, and (D)
left lateral view.
distances and arcs were then calculated using Amira 5.3
and Rapidform XOR (Inus Technology).
Breadth measurements were taken from the dural
sinus imprints at the following anatomical regions: superior sagittal sinus (SSS-B) transition curve between
superior sagittal sinus and transverse sinus, right transverse sinus, and left transverse sinus (Rosas et al.,
2008a). Each measurement was repeated three times by
EFK, and the mean value is reported in the Results section (see below, Venus sinus imprints). Several linear
measurements were also taken on the endocast following
Holloway et al. (2004b) and summarized in Table 1. Fifteen of these were used in a PCA for a dataset including
modern humans and fossil hominins, collected by one of
the authors (RH). The specimens included are listed in
Table 2, and the measurements included in the PCA are
listed Table 3. The raw measurements were corrected for
size, so that shape would be analyzed, by subtracting
the log geometric mean of all measurements for each
individual from each log-transformed measurement
(thus, generating Mossiman shape variables; Darroch
and Mosimann, 1985). We also performed the size correction using the logged endocranial volume instead of the
logged geometric mean, with very similar results (not
reported). Finally, we performed a discriminant analysis
treating the Cioclovina endocast as unknown to be classified into one of the groups used in the analysis (mod-
ern human, Neanderthal, H. erectus [s.l.], Middle
Pleistocence African, Middle Pleistocene Europeans, and
H. habilis [s.l.]) on the basis of the 15 size-corrected
measurements.
RESULTS
Anatomical Description
The virtual reconstruction of Cioclovina calvarium
allows the inspection of the endocranial surface and the
detailed anatomical description of endocranial features,
which are not visible otherwise.
The frontal sinus. The human frontal sinuses constitute two irregular air-containing cavities on the frontal bone, each communicating with the middle meatus of
the ipsilateral nasal cavity through the fronto-nasal duct
(Gray, 1918). The frontal sinus has been considered to be
functionally, physiologically, and structurally important
(Márquez, 2008), though its precise role is not clear. Our
CT imaging revealed a bilateral absence of the frontal
sinus in Cioclovina (Fig. 3A,D), in agreement with the
observations of Rainer and Simionescu (1942) on a radiograph of the specimen. The frontal sinus region in Cioclovina is occupied by dense bony tissue with small air
cells corresponding probably to a natural bony loss in
the diploe and to vascular spaces. On the contrary, the
1087
CIOCLOVINA ENDOCRANIAL MORPHOLOGY
TABLE 1. Measurements (in mm) on the Cioclovina endocast
Definitions
Measurements
Total volume
Maximum anterio-posterior chord L (mm)
Maximum anterio-posterior chord R (mm)
Maximum anterio-posterior dorsal arc L (mm)
Maximum anterio-posterior dorsal arc R (mm)
Maximum anterio-posterior lateral arc L (mm)
Maximum anterio-posterior lateral arc R (mm)
Maximum breadth chord (mm)
Maximum breadth arc (mm)
Bregma-lambda cord (mm)
Bregma-lambda arc (mm)
Bregma-basion chord (mm)
Bregma-deepest cerebellum (mm)
Bregma-asterion chord L (mm)
Bregma-asterion chord R (mm)
Bregma-asterion arc L (mm)
Bregma-asterion arc R (mm)
Bi-asterion breadth (mm)
Maximum cerebellar width (with sigmoid sinuses) (mm)
Maximum cerebellar width (without sigmoid sinuses) (mm)
Depth from vertex to lowest temporal poles (mm)
The distance of the Broca’s cap from the midsagittal plane left (mm)
The distance of the Broca’s cap from the midsagittal plane right (mm)
Maximum width across Broca’s caps (mm)
Length from frontal pole L to most posteriorly projecting part of cerebellum
(usually just under lat. sinus) (mm)
Length from frontal pole R to most posteriorly projecting part of cerebellum
(usually just under lat. sinus) (mm)
1498.53 cc
175.60
175.90
261.59
259.03
250.32
247.71
132.11
209.75
109.11
125.34
136.59
114.20
124.80
129.16
159.90
161.70
105.30
114.10
108.17
114.20
51.58
51.18
102.76
166.34
TABLE 2. Samples used in the principal
components analysis
H.habilis (s.l.): KNM 1470, KNM 1813, KNM 1805
H. erectus (s.l.): Daka, KNM 3883, KNM 3733,
Trinil, Sangiran 2, 4, 12, and 17,
Sambungmacan 3, Solo XI, Sin LE, SN IID,
SinIIL, Hexian
H. neanderthalensis: Amud 1, La Chapelle,
Spy 1 and 2, Quina 5
Middle Pleistocene Africans and Europeans:
Arago XX1, Kabwe, Irhoud 1, Sale
H. sapiens
165.16
TABLE 3. Eigenvectors of the first two principal
components
3
14
9
4
75
frontal sinus on a modern comparative specimen (Fig.
3B,E) constitutes a well-defined asymmetric cavity
extending up to high on the frontal squama. Krapina 3
(Fig. 3C,F) exhibits well-defined frontal sinuses which,
however, are mostly extended in the area of the supraorbital torus, as seems to be typical for Neanderthals (Kindler, 1960).
The imprints of the middle meningeal
vessels. The endocranial surface of the neurocranium
in the frontal and parietal regions is marked by imprints
of the middle meningeal vascular network. To avoid any
unnecessary confusion concerning the exact nature of
the imprints observed on the endocranium, we use the
term middle meningeal vessels, following Bruner and
Manzi (2008). We scored the middle meningeal system
for the derivation of the middle ramus from the anterior
(Adachi’s I), the posterior (Adachi’s II), or both the main
branches (Adachi’s III; Bruner et al., 2005; Bruner and
Manzi, 2008). In Cioclovina, the middle ramus on the
Prin1
Maximum width across Broca’s caps
Frontal pole to most posteriorly
projecting part of cerebellum
Maximum anterio-posterior chord
Maximum anterio-posterior
dorsal arc
Maximum anterio-posterior
lateral arc
Maximum breadth chord
Maximum breadth arc
Bregma-asterion chord
Bregma-asterion arc
Bregma-deepest cerebellum
Depth from vertex to
lowest temporal poles
Bregma-lambda chord
Bregma-lambda arc
Bi-asterion breadth
Maximum cerebellar width
(without sigmoid sinuses)
Prin2
0.183281
0.097837
0.097836
0.308095
0.140744
0.073028
0.350949
0.043376
0.177397
0.248980
0.291845
0.009515
0.001601
0.095816
0.094174
0.095196
0.061169
0.715061
0.105528
0.172179
0.165442
0.227054
0.470201 0.232406
0.637195 0.114941
0.287161 0.080157
0.279784 0.007707
Bilateral measurements are from the right hemisphere.
left part of the cranium seems to have been formed from
branches of both the anterior and posterior middle meningeal arteries. However, on the right side, the middle
branch of the meningeal artery appears to have derived
from the anterior branch alone (Fig. 4).
Venus sinus imprints. The anatomical details of
the occipital region and the occipital venous sinus
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KRANIOTI ET AL.
Fig. 3. Cioclovina (A, D), a female modern Greek cranium (B, E)
and the Neanderthal Krapina 3 calvaria (C, F) in frontal, superior and
lateral view. The Krapina 3 specimen was CT scanned during the European project ‘‘The Neanderthal Tools’’ (Macchiarelli et al., 2005;
Macchiarelli and Weniger, 2006) and was obtained from the NESPOS
database (htpps://www.nespos.org). The modern specimen belongs to
an adult female from a modern osteological collection in Crete,
Greece (Kranioti et al., 2008).
imprints can be clearly observed on the endocranium of
Cioclovina (Fig. 4). At the midsagittal plane, a marked
crest (corresponding to the attachment impression of the
falx cerebri) is visible. It crosses the internal occipital
protuberance through which it is connected with the internal occipital crest (the insertion of falx cerebelli). The
left cerebral fossa is deeper (more posteriorly protruding)
than the right one, and the latter is crossed by the right
sagittal sinus groove. A deep groove representing the
SSS is observed at the superior region of the occipital
squama. It becomes less marked laterally and at a distance of about 37 mm from the internal occipital protuberance deviates to the right to form the right
transverse sinus. The left transverse sinus is obvious
from roughly the midsagittal plane and forms a distinctive left transverse sinus.
The measurements of the breadths on the sinus
imprints were taken where possible. The middle portion
of the superior sagittal groove was not visible in the virtual reconstruction; therefore, this measurement was
not taken. The breadth on the transition curve between
the sagittal and the right transverse sinus groove was
about 12.4 mm. The breadths of the right and left transverse sinus grooves were 10.5 and 5.6 mm, respectively.
These values are within the normal ranges in modern
humans and human fossils (Rosas et al., 2008b). There
is an obvious right predominance of the posterior drainage system in Cioclovina.
CIOCLOVINA ENDOCRANIAL MORPHOLOGY
1089
such asymmetries. Cioclovina exhibits a protrusion of
the right occipital lobe over the left, which is mainly
attributed to the right sinus configuration creating the
impression of a right occipital petalia (Fig. 4). When the
sinus volume is accounted for, the left occipital lobe
exceeds the right one in depth and volume, suggesting
right handedness. However, a small anterior extension
of the left frontal lobe over the right one is also
observed.
Further features such as gyral and sulcal impressions
are clearly visible on the Cioclovina endocast particularly on the third inferior frontal convolution, indicating
a truly modern morphology, although definite parcellation into pars opercularis, triangularis, and orbitalis is
difficult (Fig. 5). The occipital (Fig. 6) and parietal
regions do show some convolutional relief, but it is very
difficult to be certain whether a fragment of the inferior
occipital or lunate sulcus is apparent on the left side.
There is clearly no evidence for an anteriorly located
lunate sulcus, and this region appears fully modern. On
the temporal lobe of the right side, a middle temporal
sulcus is apparent, dividing superior and inferior temporal gyri.
The estimation of the total endocranial volume for the
Cioclovina endocast was based on a virtual reconstruction using a modern human cranium as reference. The
missing part of the basicranium was reconstructed using
TPS, obtaining a total volume of the Cioclovina of
approximately 1498.53 cc.
Fig. 4. Virtual approximation of the middle meningeal vascular network and the venous sinuses drainage system in Cioclovina. (A) Left
side and (B) right side.
Endocast
A cranial endocast is a 3D replica of the endocranial
cavity of the skull. Cranial endocasts allow the observation of some of the external features of the brain. The information on circulatory and nervous system of the
endocranium as well as general shapes and volumes can
be inferred from endocasts, and such information has
been used to address the paleoneurology of fossil hominins (Connolly, 1950; Holloway, 1974; Holloway, 1983;
Holloway and Kimbel, 1986; Bruner et al., 2003; Holloway et al., 2004a; Falk et al., 2005; Bruner and Manzi,
2008).
Among the most commonly described features of the
brain hemispheres are the petalia asymmetries (protrusions of the hemispheres producing imprints on the
inner skull surface); the Yakovlenian torque (a forward
‘‘torquing’’ of the structures surrounding the right Sylvian fissure relative to their counterparts on the left);
and the asymmetry on the occipital horns of the lateral
ventricles (a deeper projection on the left occipital bone
is common; Toga and Thompson, 2003). The inferior aspect of the Cioclovina endocast allows the observation of
Morphometric analyses. The firsr two axes of the
PCA account for 56.3% of the total variance. PC1
(35.7%) roughly separates modern humans and H. erectus (s.l.) specimens, although there is overlap. Neanderthals, Middle Paleolithic specimens, and H. habilis fall
in between. PC2 (20.6%) reflects variation within the
modern human sample (Fig. 7). Neanderthals are intermediate in their position between the Homo erectus and
the modern human sample on PC1. Cioclovina falls
within the modern human range along both axes.
Although it is meaningless to calculate 95% confidence
ellipses for the very small Neanderthal sample, it is
worth mentioning that Cioclovina falls outside the Neanderthal range (Fig. 7).
Table 3 lists the eigenvectors of the first two principal
components. PC1 is influenced mainly by the bregmalambda chord and arc measurements (loading negatively) and to a lesser extent by the maximum breadth
chord, the bi-asterion breadth and the maximum cerebellar width (all loading positively). The H. erectus specimens are, therefore, characterized by endocasts with
shorter bregma-asteriod chors and arcs, as well as
greater maximum breadth chords, bi-asterion breadths,
and maximum cerebellar widths, compared to modern
human endocasts (although overlap exists in these
shapes). PC2 reflects mainly differences in the maximum
breadth arc (loading negatively), and to a lesser extent,
in the maximum anterio-posterior chord and the length
from frontal pole to most posteriorly projecting part of
the cerebellum (both loading positively). Specimens with
more negative PC2 scores, therefore, are characterized
by greater maximum breadth arcs and smaller anterioposterior lengths relative to specimens with more
1090
KRANIOTI ET AL.
Fig. 5. Convolutional details in Cioclovina’s left endocranial surface lateral view. 1. Superior temporal gyrus, 2. superior temporal sulcus, 3.
middle temporal gyrus, 4. Sylvian fissure, 5. crista galli, 6. pars triangularis, 7. pars opercularis, 8. ascending or vertical ramus of Sylvian or lateral fissure, 9. pars orbitalis, 10. superior frontal sulcus, 11. middle
frontal sulcus, 12. inferior frontal gyrus, 13. precentral sulcus, 14.
precentral gyrus, 15. horizontal ramus of the Sylvian or lateral fissure,
16. superior frontal gyrus, 17. supramarginal gyrus, and 18. inferior
portion of superior longitudinal sinus crossing right occipital pole then
becoming right lateral sinus.
positivie PC2 scores (which include the fossils in this
analysis).
The discriminant analysis classified Cioclovina as a
modern human with posterior probability of 0.59 (the
next highest probability was for H. erectus at 0.18 and
for African Middle Pleistocene hominins at 0.16). Crossvalidation classification showed that 92% of modern
humans were classified correctly (one misclassified as
H. habilis, one as Middle Pleistocene African, and four
as Neanderthals); 60% of Neanderthals were correctly
placed (with the remaining two specimens classified as
Middle Pleistocene Africans); 71.4% of H. erectus was
correctly classified (with one specimen classified as
H. habilis, one as Middle Pleistocene African, 1 as
Neanderthal and 1 as H. sapiens).
DISCUSSION
The frontal sinus morphology has been widely discussed in a phylogenetic context and emphasis has been
given to its implication in anatomical function and climatic adaptation (e.g., Márquez, 2008). However, the difficulties in ascertaining their homology in fossils impede
the understanding of their phylogenetic significance.
Furthermore, among modern humans, the degree of anatomical variability reported for several temporally and
spatially distinct populations (Buckland-Wright, 1970;
Kupczik, 1999; O’Higgins et al., 2006) is so high that the
anatomy of the frontal sinus is considered a unique cranial
feature extensively used in forensic identification (Quatrehomme et al., 1996; Christensen, 2004; Cox et al., 2009).
Frontal sinus agenesis in Cioclovina as extrapolated by the
CT reconstruction confirms the observation of Rainer and
Simionescu, (1942) inferred by means of radiography. This
condition is rare in some populations of modern humans,
Fig. 6. Convolutional details in Cioclovina’s endocranial surface occipital view. 1. Inferior occipital sulcus, 2. retrocalcarine sulcus, 3.
tempero-occipital incisure, 4. Left lateral sinus, 5. confluence of sinuses,
6. Inferior portion of superior longitudinal sinus crossing right occipital
pole then becoming right lateral sinus, 7. left occipital pole, and 8.
post-parietal groove.
but frequent in others, and is generally not observed in
Neanderthals. The absence of the frontal sinus has been
reported at a frequency of 95% in a Mesolithic population
from Sudan (Greene and Scott, 1973), but 5% in Australians of European extraction (Schuller, 1943), while in sample of Pleistocene–Early Holocene fossils from Tanzania,
two of five specimens exhibited extremely small frontal
sinuses (Mumba VI, Strauss III; Kupczik, 1999). The high
variability in modern human frontal sinus configurations
has been attributed, among other factors, to the extent of
distribution of masticatory stresses on the face (Greene
and Scott, 1973). Neanderthals on the other hand appear
heavily pneumatized, although pneumatization appears to
be mainly constrained to the supraorbital torus region
(Fig. 1; Kindler, 1960).
The middle medial meningeal system is thought to
have undergone marked changes during human evolution (Grimaud-Hervé, 2004), possibly due to its major
role in metabolism and thermoregulation (Bruner and
Manzi, 2008). In modern humans, the anterior and middle rami are usually predominant compared to the less
developed posterior branch, although this pattern is
variable (Grimaud-Herve, 2004). The anterior ramus is
found to be more (e.g., Gibraltar 1 and 2) or equally
(e.g., Le Moustier) predominant to the posterior ramus
in Neanderthals and Pre-Neanderthals (Grimaud-Herve,
2004). In Cioclovina, there is a bilateral asymmetry in
the pattern of the middle meningeal vessels. On the left
side anterior and posterior rami seem to be equally dominant both giving rise to the middle ramus. However, on
the right side, the anterior branch is more predominant
and gives rise to the middle ramus, with which it shares
a large number of anastomoses. While the former pattern characterizes modern humans, the latter is
observed in both modern humans and Neanderthals.
CIOCLOVINA ENDOCRANIAL MORPHOLOGY
1091
Fig. 7. Principal components analysis PC1 and PC2. A convex hull is drawn for the Neanderthal sample (red polygon).
A recent comparative study of venous sinus topology
in human fossils did not find a straightforward relationship between the venous sinus shape and brain size in
Neanderthals and modern humans (Rosas et al., 2008b).
Cioclovina exhibits a clear right predominance of the
posterior drainage system, with breadth values that fall
within the normal range of both modern and other Pleistocene fossil humans (Rosas et al., 2008b).
Hemispheric asymmetries are commonly thought to
reflect hemispheric dominance and handedness in modern humans. In Cioclovina, the right occipital lobe gives
an impression of a posterior protrusion, but careful observation reveals that this protrusion results from the
configuration of the right venous sinus. The left occipital
lobe is larger than the right one in both width and total
volume, suggesting right handedness. The slight anterior projection of the left frontal lobe is of minor importance, as the distance of the Broca’s cap from the
midsaggital plane is almost equal in both sides of the
endocast (see Table 1). Therefore, we suggest that left
hemispheric dominance and right handedness is the
most likely interpretation. The Cioclovina endocranial
volume is well within the range of modern humans, and
falls near the average value reported for modern people.
Finally, a PCA analysis of 15 size-corrected measurements again places the shape of the Cioclovina endocast
with that of modern humans. It is further classified as a
modern human based on a discriminant analysis of the
same size corrected measurements.
modern human pattern in this Upper Paleolithic European individual. The specimen displays some idiosyncratic features, such as frontal sinus agenesis and rightleft asymmetry in the middle meningeal vessel pattern.
However, as far as can be determined, its gyral and sulcal configuration is modern human-like, its estimated
endocranial volume falls well within the modern human
range of variation, and its endocranial shape places it
with modern humans rather than fossil hominins,
including Neanderthals.
ACKNOWLEDGEMENTS
The CT scan of the modern Greek used in Fig. 1B,D
was obtained through funding from the Institute for Aegean Prehistory. Concerning the modern human reference sample, the authors thank Antonio Rosas González
(Museo Nacional de Ciencias Naturales, Madrid, Spain)
and G. W. Weber (Department of Anthropology, Vienna,
Austria) for access to CT–data. The ‘‘NESPOS Database
[2009] Neanderthal Studies Professional Online Service
(http://www.nespos.org) was used to produce Fig. 1C,F.
E.F. KRANIOTI thanks Antonio Garcı́a Tabernero for
his most valuable advice on 3D virtual tools. Special
thanks to David Ramon for his contribution in preparing
the 3D virtual approximation of the middle meningeal
vascular network and the venous sinuses drainage system, illustrated in Fig. 2A,B.
CONCLUSIONS
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