Download New fossil hominid calvaria from Indonesia

THE ANATOMICAL RECORD 262:344 –368 (2001)
New Fossil Hominid Calvaria From
Indonesia—Sambungmacan 3
SAMUEL MÁRQUEZ,1– 4 KENNETH MOWBRAY,5,6 G J SAWYER,5
TEUKU JACOB,7 AND ADAM SILVERS8
1
Departments of Cell Biology and Anatomy, Mount Sinai School of Medicine, New York
2
Department of Anthropology, City University Graduate Center, CUNY, New York
3
Department of Anthropology, Lehman College, City University of New York, New York
4
New York Consortium in Evolutionary Primatology, Department of Anthropology,
The Graduate School, CUNY, New York
5
Division of Anthropology, American Museum of Natural History, New York
6
Department of Anthropology, Rutgers University, New Jersey
7
Laboratory of Bioanthropology and Paleoanthropology, Faculty of Medicine,
Gadjah Mada University, Yogyakarta, Indonesia
8
Department of Radiology, Mount Sinai School of Medicine, New York
ABSTRACT
A morphologically distinct partial calvaria of Homo cf. erectus from Java, Indonesia is described. The fossil hominid
Sambungmacan 3 (Sm 3) was first discovered in 1977 from the banks of the Solo River near the village of Poloyo,
Sambungmacan district, in central Java. It was later recovered in a New York City natural history establishment in 1999
and quickly returned to the Indonesian authorities. Examination of Sm 3 shows that the calvaria is well preserved with only
portions of the cranial base missing. The most striking characteristics of Sm 3 include: the presence of a vertically rising
forehead, more open occipital/nuchal and frontal angles, a more globular vault, and a cranial capacity within the Homo
erectus range. Most notably absent in Sm 3 are a number of the classic characters attributed to Homo erectus, such as a
strongly expressed angular torus and a continuous supratoral sulcus. The absence of such characters would normally place
the calvaria outside the range of Homo erectus (sensu stricto), however, overall quantitative and qualitative morphological
assessments of Sm 3 place it within the Homo erectus spectrum. The combination of the morphological characters in Sm 3
may be interpreted in several ways: 1.) the known cranial variation of H. erectus from Indonesia and China is extended; 2.)
this calvaria shows evidence of evolutionary change within H. erectus; or 3.) more than one species of Homo existed in the
(presumed) Middle Pleistocene of Java.) Anat Rec 262:344 –368, 2001. © 2001 Wiley-Liss, Inc.
Key words: Homo erectus; Java; Sm 3; vertically rising frontal; open occipital/nuchal plane angle;
cranial capacity
The “rediscovery” of a morphologically distinct partial
calvaria of Homo cf. erectus from Indonesia was announced in New York on August 29, 1999. Its recent
history is somewhat unclear (discussed below), but its
unique features were quickly recognized in the summer of
1999 when it was brought to the American Museum of
Natural History (AMNH). During its eight-week stay at
the AMNH, we felt it was important to thoroughly examine the fossil in order to document its morphology with
written descriptions, photographs, and computer tomography (CT) imaging, and subsequently report our findings
as a preliminary chronicle of its recovery (Mowbray et al.,
2001). Accompanying this description are two articles involving a paleoneurological assessment of the specimen
(Broadfield et al., 2001), and a brief interpretive study
using three-dimensional coordinate data and comparative
morphological observations on selected specimens attrib©
2001 WILEY-LISS, INC.
uted to African and Asian Homo erectus and extant Homo
sapiens (Delson et al., 2001).
According to several sources, Sm 3 was discovered in
1977 from the banks of the Solo River near the village of
Poloyo, Sambungmacan district, Sragen country, in central Java, some 50 km north of the Sangiran Dome. The
Grant sponsor: National Science Foundation; Grant number:
SBR9634519; Grant sponsor: National Institutes of Health;
Grant number: F31-DC00255-01.
Correspondence to: Samuel Márquez, Department of Cell Biology and Anatomy, Mount Sinai School of Medicine, One Gustave
L. Levy Place, Box 1007, New York, NY 10029.
E-mail: [email protected]
Received 12 June 2000; Accepted 20 December 2000
Published online 28 February 2001
SM 3 CALVARIA
345
Fig. 1. Map of Indonesia with the inset highlighting the site of Poloyo, Java where Sm 3 was first reported
to have been found. Map courtesy of Angela M. H. Schuster, Archaeology Magazine.
calvaria was reportedly discovered by miners excavating
sand from the Solo River for use as construction material.
Although the exact location and date of discovery cannot
be confirmed (Jacob, 1999), it is thought that it may have
been discovered near Ngadirejo in Sambungmacan between the villages of Chemeng and Poloyo (Fig. 1). The
calvaria was purchased from the discoverer by an unknown agent and eventually ended up in an antiquities
shop in Jakarta. In 1997, Dr. Boedhihartono, an Indonesian paleoanthropologist, was invited to examine the specimen in the antiquities shop in order to determine its
authenticity; he published a brief description and provided some measurements and photographs (Boedhihartono, 1998). In the spring of 1999 the specimen “surfaced”
in Maxilla & Mandible, Ltd., a New York City natural
history establishment owned by Henry Galiano. Galiano,
who is quite familiar with the techniques used for cleaning
original fossils from his days in the Department of Vertebrate Paleontology at the AMNH, cleaned the external
surface of the calvaria and removed the matrix from the
internal surface for future geological study. In late June,
Galiano brought the fossil to the AMNH for examination.
While I. Tattersall, K. Mowbray, G.J. Sawyer, and E.
Delson examined the calvaria to determine its authenticity, it was learned from Dr. Hisao Baba of the National
Science Museum in Tokyo, Japan, and Professor Teuku
Jacob of the Gadjah Mada University, Yogyakarta, Indonesia, that the calvaria might be the same fossil hominid
that an Indonesian antiquities dealer had tried to sell the
previous year in Jakarta. After receiving a partial copy of
Boedhihartono’s 1998 report with photos of the calvaria, it
became evident to us that the fossil hominid under examination and the calvaria from Jakarta were the same
specimen. Accordingly, Mr. Galiano contacted the Indonesian government and arranged to return the fossil to
them. On August 29, 1999, in a formal ceremony conducted at Maxilla & Mandible Ltd., Mr. Galiano presented
the specimen to Professor Jacob and various representatives of the Indonesian government. In return, Mr.
Galiano was honored with an award from the Indonesian
government in recognition of his generosity and thoughtful commitment to science. While in New York, Professor
Jacob temporarily assigned the designation of Poloyo 1
(Pl-1) (Mowbray et al., 2000) to the specimen but, once
back in Java, he changed the accession code to Sambungmacan 3 (Sm 3) in recognition of its provenance in the
same region as the calvaria Sm 1 (Jacob, 1975) and tibial
fragment Sm 2 (Baba et al., 1990 and Matsu’ura 2000).
The precise sites of discovery may be designated Sambungmacan Locality 1 and Locality 2.
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MÁRQUEZ ET AL.
TABLE 1. Metrical descriptions and definitions (taken from Wood, 1991)
No.
Description
1.
2.
3.
Length (glabella—opisthocranion) (C)
Minimum frontal breadth
Maximum bi-parietal breadth
4.
Maximum bi-temporal breadth
5.
6.
Biporionic breadth (C)
Supramastoid crest breadth (C)
7.
Maximum mastoid breadth at base (C)
8.
9.
10.
11.
12.
13.
14.
15.
16.
Glabella—bregma (C)
Glabella—bregma (A)
Bregma—left pterion (C)
Bregma—left pterion (A)
Bregma—right pterion (C)
Bregma—right pterion (A)
Parietal sagittal length (C)
Parietal sagittal length (A)
Parietal right temporal length (C)
17.
18.
Parietal right temporal (A)
Parietal left temporal length (C)
19.
20.
Parietal left temporal (A)
Parietal coronal breadth (C)
21.
Parietal coronal breadth (A)
22.
Parietal right lambdoidal length (C)
23.
Parietal right lambdoidal length (A)
24.
Parietal left lambdoidal length (C)
25.
Parietal left lambdoidal length (A)
26.
27.
28.
29.
30.
31.
32.
Bregma right asterion (C)
Bregma right asterion (A)
Bregma Left asterion (C)
Bregma Left asterion (A)
Lambda—inion (C)
Lambda—inion (A)
Inion—opisthion
33.
34.
35.
36.
37.
Occipital Sagittal length (C)
Occipital Sagittal length (A)
Biasterionic breadth (C)
Biasterionic breadth (A)
Width temporal gutter
38.
39.
Width temporal gutter
Vertical distance of supraorbital torus
40.
Vertical distance of supraorbital torus
41.
Anteroposterior thickness of right
supraorbital torus (C)
42.
Anteroposterior thickness of right
supraorbital torus (A)
43.
Anteroposterior thickness of left
supraorbital torus (C)
Definition
Chord distance
Minimum chord distance between frontotemporale (ft-ft)
Breadth across homologous points on the parietal bone at the
site of maximum breadth.
Breadth across homologous points on the temporal squama at
the site of maximum breadth.
Chord distance
Chord distance across the maximum projection of the
supramastoid crests
Chord distance across the points of maximum projection on the
mastoid process, wherever that occurred, but excluding the
supramastoid crests.
Chord distance
Arc length
Chord distance
Arc length
Chord distance
Arc length
Chord distance
Arc length
Chord distance along the temporal border of the intact parietal
(sphenion—asterion)
Arc length along the temporal border of the intact parietal
Chord distance along the temporal border of the intact parietal
(sphenion—asterion)
Arc length along the temporal border of the intact parietal
Chord distance along the coronal border of the intact parietal
(bregma—sphenion)
Arc length along the coronal border of the intact parietal
(bregma—sphenion)
Chord distance along the lambdoid border of the intact parietal
(lambda—asterion)
Arc length along the lambdoid border of the intact parietal
(lambda—asterion)
Chord distance along the lambdoid border of the intact parietal
(lambda—asterion)
Arc length along the lambdoid border of the intact parietal
(lambda—asterion)
Chord distance
Arc length
Chord distance
Arc length
Chord distance
Arc length
Opisthion not clearly demarcated but measure approximates the
posterior border of foramen magnum
Chord distance
Arc length
Chord distance
Arc length
Maximum distance from the outer wall of the temporal squama
at the anterior end of the root of the zygomatic process to the
outer lip of the process at that location.
Left damaged
Chord distance taken at the highest point of the left supraorbital
margin.
Chord distance taken at the highest point of the right
supraorbital margin.
Chord distance, taken from above, between the most anterior
projection of the torus at the highest point on the superior
orbital margin and the posterior limit of the torus, or the
shallowest point in the post-toral sulcus.
Arc length, taken from above, between the most anterior
projection of the torus at the highest point on the superior
orbital margin and the posterior limit of the torus, or the
shallowest point in the post-toral sulcus.
Same as in 41.
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SM 3 CALVARIA
TABLE 1. Metrical descriptions and definitions (taken from Wood, 1991) (continued)
No.
43.
Description
45.
Anteroposterior thickness of left
supraorbital torus (C)
Anteroposterior thickness of left
supraorbital torus (A)
Frontal torus breadth (C)
46.
Frontal torus breadth (A)
47.
Mandibular fossa length (C)
48.
Mandibular fossa length (A)
49.
Mandibular fossa breadth (C)
50.
Mandibular fossa breadth (A)
51.
Mandibular fossa depth
44.
Definition
Same as in 41.
Same as in 42.
Maximum chord distance across the frontal toral region. The
termini for this measure usually lie lateral to frontotemporal
orbitale.
Arc length across the superior aspect of the torus as defined in
45.
Only left is sufficiently preserved. Minimum chord distance
between the tympanic plate and the most inferior projection of
the articular eminence; taken midway along the breadth
measurement
Arc distance between the termini described above. Only left fossa
was measured.
Minimum chord distance in the coronal plane between the tip of
the entoglenoid process and the most lateral extent of the
articular margin on the articular eminence.
Arc distance between the termini described above. Only left fossa
was measured.
Maximum perpendicular distance between an imaginary line
connecting the most inferior projection of the articular
eminence and the tip of the postglenoid process, and the roof of
the mandibular fossa.
MATERIALS AND METHODS
This article focuses upon the description of the original
fossil of Sm 3 and reports a series of standard morphometric measurements (see Table 1). Quantitative measures
that take into account clearly identifiable anatomic landmarks and craniometric points are reported in Table 2.
The description and discussion of measurements found in
Results are grouped by regions following a protocol developed by Schwartz and Tattersall (in preparation) that
strives to encompass all aspects of available skull anatomy, while ensuring the utilization of a uniform descriptive nomenclature that purposely lacks systematic implications. The subsections include: Sex Determination,
Supraorbital Region, Cranial Roof, Cranial Walls, Cranial
Rear, Cranial Base, Cranial Sutures and Thickness, Anterior Endocranial Compartment, Middle Endocranial
Compartment, Posterior Endocranial Compartment, Sinus Drainage System, and Middle Meningeal Vessels.
Two subsections (sex determination, cranial sutures,
and cranial thickness) not included in the Schwartz and
Tattersall protocol are incorporated into the description
and require brief explanations. Sex determination in the
human fossil record is based on the sexual dimorphism of
modern humans (and other primates), that may be attributed to hormonal development as represented by muscle
attachment to bone. Marked nuchal rugosities, prominent
surpraorbital tori, and strong temporal lines are generally
representative of males, while minimal expression of
these characters is indicative of females. Problems regarding the accuracy of sexing skeletal material arise when the
range of variation for a particular population is unknown,
when only one skeletal element is being assessed, with
qualitative vs. quantitative approaches, and with “experience” vs. statistical “standardization” (Krogman and
Iscan, 1986). These factors may explain why certain characters might not all score as the same sex. Following in the
tradition of a number of workers (e.g., Santa Luca, 1980;
Weidenreich, 1943; Wolpoff, 1999), the precarious nature
of applying these techniques to the fossil record was taken
into account when assessing sex.
The description of cranial sutures in humans is well
documented (Todd and Lyon, 1925), and students of human variation and evolution have used the degree of sutural closure as an age indicator of when death occurred.
However, the application of these techniques using adult
specimens, fossil or recent, is not without controversy and
debate (Brooks, 1955; Buikstra and Ubelaker, 1994;
Meindl and Lovejoy, 1985; Perizonius, 1984; Singer,
1953). For example, Weidenreich (1951) evaluated the
Ngandong cranial assemblage and estimated that nearly
half of the specimens recovered were juveniles based primarily on incomplete ectocranial synostosis. Antón and
Franzen (1997) argue convincingly that other cranial features, such as relative cranial development and cranial
thickness, should be included during fossil crania examination, rather than relying solely on the lack of overall
sutural closure to estimate age. With this caveat in mind,
a description and a scoring of the degree of sutural closure
are reported (Table 3) along with measurements of cranial
thickness (Table 4).
To facilitate our examination of endocranial, ectocranial
and pneumatization morphologies, we utilized CT imaging of the fossil specimen, and a first generation hemisected cast. Quantitative descriptions are based on
standard measurements taken with polycarbonate vernier
calipers, spreading calipers, and a flexible cloth tape.
Frontal angle and vertex of the calvaria were derived with
the specimen in the Frankfurt Horizontal (FH) based on
Weidenreich (1951) and Santa Luca (1980) estimated orbital height measure of 38 mm in order to approximate
infraorbitale since the calvaria lacked its orbital floors.
Endocranial volume determination. Endocranial
volume was measured by two different methods: seed fill-
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MÁRQUEZ ET AL.
TABLE 2. Calvaria dimensions of Sm 3 (in millimeters)
1. Length (glabella—opisthocranion)
2. Minimum frontal breadth
3. Maximum bi-parietal breadth
4. Maximum bi-temporal breadth
5. Biporionic breadth
6. Supramastoid crest breadth
7. Maximum mastoid breadth at base
8. Glabella—bregma (C)
9. Glabella—bregma (A)
10. Bregma—left pterion (C)
11. Bregma—left pterion (A)
12. Bregma—right pterion (C)
13. Bregma—right pterion (A)
14. Parietal sagittal length (C)
15. Parietal sagittal length (A)
16. Parietal right temporal length (C)
17. Parietal right temporal (A)
18. Parietal left temporal length (C)
19. Parietal left temporal (A)
20. Parietal coronal breadth (C)
21. Parietal coronal breadth (A)
22. Parietal right lambdoidal length (C)
23. Parietal right lambdoidal length (A)
24. Parietal left lambdoidal length (C)
25. Parietal left lambdoidal length (A)
26. Bregma right asterion (C)
27. Bregma right asterion (A)
28. Bregma left asterion (C)
29. Bregma left asterion (A)
30. Lambda—inion (C)
31. Lambda—inion (A)
32. Inion—opisthion
33. Occipital Sagittal length (C)
34. Occipital Sagittal length (A)
35. Biasterionic breadth (C)
36. Biasterionic breadth (A)
37. Temporal gutter width (right)
38. Temporal gutter width (left)
39. Vertical distance of supraorbital torus (left)
40. Vertical distance of supraorbital torus (right)
41. Anteroposterior thickness of right supraorbital torus (C)
42. Anteroposterior thickness of right supraorbital torus (A
43. Anteroposterior thickness of left supraorbital torus (C)
44. Anteroposterior thickness of left supraorbital torus (A)
45. Frontal torus breadth (C)
46. Frontal torus breadth (A)
47. Mandibular fossa length (C) (only left side is sufficiently preserved)
48. Mandibular fossa length (A) (only left side is sufficiently preserved)
49. Mandibular fossa breadth (C)
50. Mandibular fossa breadth (A)
51. Mandibular fossa depth
ing with oil rapeseeds and water displacement. Using the
seed-filling method, an initial endocranial volume was
obtained directly from the calvaria without any attempt to
reconstruct its missing cranial base. A second endocranial
volume was derived by reconstructing its cranial base
with the use of inert modeling clay. Continual gentle tapping of the calvaria during the filling process ensured
seeds were fully packed and settled. Before and after each
seed-filling, the calvaria was weighed with an electronic
scale (to 0.1 gm). The procedure was repeated five times
for both unreconstructed and reconstructed fossil. Weight
data were then transformed to volumetric measurements
(in milliliters) by linear regression. A reference regression
line (r2 ⫽ 0.99 P ⬍ 0.001) was created by using the weights
178.5
101
126.5
127.5
131.5
145.5
126.5
103
106
87
98
87.5
100
98
105
59.7
59.9
62.4
63
72.5
73
70.5
71
71.5
75
125.5
140
123.5
140
50.5
54
40.1
80.5
96
118
126
6.4
—
12.5
13.5
5.9
32
25.2
30
111.2
138
20
21
18.5
20
14.2
for nine known volumes of seeds (5 ml to 45 ml at 5 ml
intervals), whereby each was measured twice using two
differently shaped graduated cylinders. Rapeseeds were
also introduced into the calvaria and measured in a graduated cylinder. No statistical significant differences were
recorded for the two seed-filling techniques. Rhodorsil威
silicon rubber endocasts were made from the original Sm
3 specimen and endocast reconstructions were displaced
in water to calculate endocranial volume. Results from
seed filling and water displacement techniques are shown
in Table 5.
Imaging modalities. CT imaging was performed using a HiSpeed CT/i scanner (GE Medical Systems, Mil-
349
SM 3 CALVARIA
TABLE 3. Assessment of ectocranial suture closure
Midline
Sagittal
1: pars bregmatica
2: pars verticis
3: pars obelica
4: pars lambdica
Coronal
1: pars bregmatica
2: pars complicata
3: pars stephanica
4: pars pterica
Lambdoid
1: pars lambdica
2: pars intermedia
3: pars asterica
Parieto-mastoid
Occipito-mastoid
Squamous
Spheno-frontal
Spheno-temporal
Spheno-parietal
Left
Right
0
0
0
0
0
0
eroded
0
0
1
0
eroded
0
0
0
0
eroded
3
1
0/1
0
0
eroded
0
eroded
eroded
1
n/a
0
TABLE 4. Calvaria thickness of Sm 3 in millimeters
Glabella
Glabella—Bregma midpoint
Bregma
Bregma-Lambda midpoint
Bregma to lambda midpoint
Lambda
External occipital
protuberance
Pterion (left)
Pterion (right)
Pterion
Asterion (left)
Asterion (right)
Stephanion (left)
Stephanion (right)
Parietal eminence (left)
Parietal eminence (right)
21.0
8.5
11
10
11 (adjacent to left parietal)
11 (adjacent to right parietal)
11.5
16
12.5
12
7.5
15
15
7
7.5
12
12
waukee, WI) at the Mount Sinai Hospital/NYU Medical
Center. Helical scanning was used with images reconstructed at 1 mm intervals. The CT machine specifications
were a 25 cm field of view (DOV), 140 kV, and 170 mA with
a 1:1 pitch helical scan. The images were processed on an
Advantage Windows Workstation (ADW) (GE Medical
Systems) using ADW 3.1 software for surface and volume
rendering and to reconstruct other localized three-dimensional structures employing sagittal and coronal reformations.
RESULTS
Preservation and Condition of Sambungmacan 3
The calvaria shows excellent preservation in both ectocranial and endocranial anatomy with no distinctly noticeable taphonomic deformities. The blackish-gray calvaria is heavily mineralized, extremely well preserved,
and shows no evidence of either complete fracture or any
bone perforation. There are scratches throughout the ectocranial portion of the calvaria which require further
investigation but do not appear to be the result of speci-
TABLE 5. Endocranial volume data from Sm 3
Seed filling without
reconstructing
basicranium
Seed filling with
reconstructing
basicranium
870 cc
890 cc
Average water
displacement of
reconstructed
endocast
917 cc
men cleaning. The neurocranium is almost complete,
while the splanchnocranium and major portions of the
cranial base are missing (see Figs. 2–7). Both temporal
lines are discernible and the amount of sagittal keeling
can be seen anteriorly at bregma. The orbital roofs are
relatively complete while an area of postmortem damage
inferior to glabella serves as a portal into a possible frontal
sinus region (Fig. 8). The mandibular fossae, temporal
planes, and mastoids are well preserved, but only the left
external acoustic meatus is present. Both mastoid tips are
broken, revealing varying degrees of pneumatization. The
majority of the sphenoid, basilar, and condylar portions of
the occipital and petrous portions of the temporal bones
are missing. The nuchal and occipital planes are sufficiently preserved on the external and internal surfaces to
determine nuchal rugosity, the angle between the two
planes, and to provide information about the posterior
cranial fossa. Sutures remain open (see Table 3) on the
ectocranial surface of the vault, however, the endocranial
surface reveals sutural closure but not complete obliteration. The degree of cranial sutural closure and overall
vault thickness suggests that this individual was most
likely a young adult when death occurred (see Antón,
1999).
Sex Determination
The calvaria exhibits a suite of characters that makes
sex determination difficult to ascertain. In this regard,
male characters include well-developed and elongated suprameatal crests, a well-developed occipital protuberance,
and pronounced lateral arcus superciliaris. Characters
attributed to females include an overall small calvaria,
lack of strongly developed superior and inferior temporal
lines, a bulbous frontal region, and a depressed glabellar
region. Although its mosaic of characters may be too ambiguous to allow us to properly determine the sex of Sm 3,
the overall smaller size and somewhat less rugose expression of features in Sm 3, as compared to most presumed
male Javanese fossils (Santa Luca, 1980; Weidenreich,
1951), suggest a female identification (see also Delson et
al., 2001).
Overall Appearance of Sm 3
The calvaria is relatively short and broad with a steeply
rising frontal and a fairly open angle between the occipital
and nuchal planes resulting in a relatively globular appearance in side view. In lateral profile, the vault shows
little supraorbital distension while exhibiting a globular
shaped morphology (see Figs. 2 and 3). Based on CT scans
and hemisected casts, the forehead rises steeply before
arching posteriorly. Maximum length of the calvaria (glabella to opisthocranion) measures 178.5 mm. Maximum
breadth of 145.0 mm across the squamous temporals, and
minimum frontal breadth of 101.0 mm. A cranial index
(CI) of 81 further indicates a broad-headed individual.
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MÁRQUEZ ET AL.
Fig. 2.
Right lateral view of Sm 3 calvaria with original above and cast seen below.
SM 3 CALVARIA
Fig. 3.
Left lateral view of Sm 3 calvaria with original above and cast seen below.
351
352
MÁRQUEZ ET AL.
Fig. 4.
Superior view of Sm 3 calvaria with original above and cast seen below.
SM 3 CALVARIA
Fig. 5.
Inferior view of Sm 3 calvaria with original above and cast seen below.
353
Fig. 6.
Anterior view of Sm 3 calvaria with original above and cast seen below.
SM 3 CALVARIA
Fig. 7.
Posterior view of Sm 3 calvaria with original above and cast seen below.
355
356
MÁRQUEZ ET AL.
Fig. 8.
Photograph of inferior view showing frontal bone region.
Fig. 9. A three-quarter view of a three-dimensional reconstruction of Sm 3. Note the steeply rising frontal
squama with no supratoral extension at the midline.
Supraorbital Region
The lateral margins of the supraorbital region of Sm 3
markedly project anteriorly, whereas the medial portions
protrude minimally in the same direction. The marginal
surface above each orbit is continuous and relatively uniform in vertical thickness. The two orbital margins, however, are not completely confluent across glabella. As such,
glabella is slightly depressed when viewed superiorly, and
lacks a distinct angle or bony bulge that clearly delineates
it superiorly. The lateral surfaces of the orbital roofs roll
smoothly anteriorly, superiorly, and subsequently posteriorly where they form flat plateaus prior to gradually
sloping into the lateral walls of the frontal squama. The
medial surface of the left orbital roof (the right side is
damaged on its inferior surface), however, rolls smoothly
anteriorly and superiorly to become somewhat flat and
slightly angled as it forms the supraorbital ridge. The
medial surfaces of the supraorbital region, unlike the lat-
eral surfaces, quickly meet the steeply rising slope of the
frontal squama (Fig. 9).
A distinct supraorbital notch occurs on the superior
margin of the left orbital region and causes a superoinferior thinning in this area. The right side could not be
assessed. The middle supraorbital region shows only a
slight supratoral sulcus, but both lateral margins have
moderate depressions that may be interpreted as sulci
(Fig. 10). Post-orbital (PO) constriction is minimal, as
reflected by a PO index of 88 (see Fig. 7 in Delson et al.,
2001), which is calculated by the (minimum frontal
breadth measured at FT-FT/maximum breadth of the supraorbital ridge ⫻ 100).
Postmortem damage to the inferior portion of the
frontal bone exposes the outer and inner tables of the
region with the intervening space filled with matrix.
Whether the present infill reflects the replacement of
trabecular bone or of empty space could not be deter-
SM 3 CALVARIA
357
30 mm superior to glabella and continues through
bregma. Sagittal keeling progresses along most of the
sagittal suture, tapering off approximately 34 mm anterior to lambda (Fig. 13).
Cranial Walls
Fig. 10. A superior view of a three-dimensional reconstruction showing the lateral wing extension of the supratorus.
mined. Macroscopic imaging of the frontal did not reveal
any clear demarcation between matrix infill and mineralized bone. CT imaging of the region suggests that
sinus cavities might exist as seen in the very subtle
differences of opacity (see Fig. 11A,B,C). These voxel
intensity differences, however, could just as likely be
from the porous nature of the trabeculae meshwork that
may have existed previously. Subsequent to its return
to Java, the infill has been removed, revealing an apparently well-developed frontal sinus morphology (Jacob, personal communication).
Just above the right supraorbital ridge on the ectocranial surface of the frontal squama are a series of raised
interconnecting bony nodules. These osteogenic calluses
form a C-shaped narrow ridge of raised bone that is contained within a 20 mm2 area. A few less prominent unconnected nodules also rise up superior to glabella. Examination of the calvaria in its entirety reveals that the
raised calluses are concentrated on the periosteum of the
frontal bone alone. It is unclear whether they are the
result of a nonlethal trauma or of a localized infection that
had healed before death.
Cranial Roof
Beginning at glabella and ending at bregma, the frontal
squama in sagittal profile presents a moderate arc. At
bregma, the vault begins a symmetrical, curved, backward
descent until it reaches opisthocranion. Maximum cranial
height of the sagittal profile was estimated to lie posterior
to bregma. The metopian– glabella vector formed a 75.3°
angle with the estimated FH (Fig. 12). Maximum cranial
breadth occurs on the laterally protrusive supramastoid
crests. A moderate frontal and a prominent sagittal keel
are clearly defined. Frontal keeling begins approximately
In coronal profile, at the mastoid region, the walls of the
calvaria are mainly parabolic in shape. From the base of
the mastoids, the walls initially slope laterally only to
quickly rise vertically until they cross the temporal lines,
after which the walls curve inward towards the midline
(Fig. 14). The temporal lines are weakly expressed on both
sides of the calvaria. They originate from the lateral wing
of the superior orbital margins and course posteriorly in
low arcs, ending near asterion. The posterior root of the
zygomatic process of the right temporal bone originates
anterior to the external auditory meatus while the left
zygomatic process is missing. Both sides have confluent
suprameatal and supramastoid crests. On the right, the
root of the zygomatic process is continuous with the suprameatal crest. Both suprameatal crests roof over the
external auditory meatus. The supramastoid crests are
prominent and sweep markedly upward. The left parietal
shows a sharp oval depression measuring 1.1 mm in maximum length with three groups of parallel scratch marks.
Two of these groups radiate diagonally from the oval
“puncture” mark in a posterior direction, while the third
group is situated closer to the sagittal–lambdoidal suture.
The mastoid processes are of moderate to small size and
have a slightly narrow base. The tips of both mastoid
processes are broken off, exposing matrix-filled air cells.
The left mastoid process is moderately excavated while
matrix fills the right process to its outer rim. In inferior
view, the processes are triangular with their internal
peaks angled obliquely anterior. Their lateral surfaces
(mastoid crests) are slightly convex. The left external
acoustic meatus is round in outline with its tympanic
portion contributing significantly to the deep posterior
wall of the mandibular fossa.
Only the superiormost portions of the greater wings of
the sphenoid are present with the left side clearly intruding between the temporal and frontal bones. This configuration helps form an acute sphenoidal angle of the parietal bone. The squamous portion of temporal bone is
moderately long (approximately 1/3 of the overall cranial
length). Its maximum height occurs anteriorly, well before
its midpoint. This causes its superior border to slope posteriorly until reaching a deeply incised parietal notch.
Cranial Rear
The sagittal profile of the posterior region is moderately
curved with a relatively open angle where the occipital
and nuchal planes intersect. The posterior end of the
sagittal keel superior to lambda is relatively flat. At the
lambdoidal suture, incomplete ectocranial synostosis between the parietals and the occipital produces moderate
relief. Continuing inferiorly from lambda, the occipital
squama is very slightly curved, approximating an almost
flat surface. At the midpoint between the superior and
highest nuchal lines the occipital squama presents a moderate buildup of bone. Here, the nuchal plane undercuts
the occipital plane forming a 117.7° angle at opisthocranion (Fig. 15).
From a posterior view, the superior nuchal lines exhibit
well-defined bilateral arches that converge at the inferi-
Fig. 11. A: A close-up of the frontal bone from figure 11B showing
either some vacuities of the remnant cancellous bone or frontal pneumatization, which has been somewhat obfuscated by mineral infill. B: An
arial view of Sm 3 with arrows pointing to the pneumatized regions of the
frontal and occipital bones. C: A close-up of the occipital bone region
from Figure 11B illustrating cancellous bone.
Fig. 12.
Lateral view of Sm 3 showing the metopian-glabella and FH vectors forming a 75.3° frontal angle.
Fig. 13.
Three quarter view of a three-dimensional reconstruction showing midsagittal keeling.
Fig. 14. Anterior view of a three-dimensional CT reconstruction coronal slice through the region of the
mastoids of Sm 3 illustrating its cranial wall shape.
Fig. 15. A sagittal three-dimensional CT reconstruction of Sm 3 showing how the nuchal plane undercuts
the occipital plane forming a 117.7° angle at opisthocranion.
Fig. 16. A posterior three-dimensional CT reconstruction view of Sm 3 revealing the detailed bilateral
arches of the superior nuchal lines that converge at the inferiorly projecting external occipital protuberance.
Fig. 17.
A close-up posterior view of Sm 3 showing a wormian bone at lambda.
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MÁRQUEZ ET AL.
Fig. 18.
bone.
A right posteroinferior three-quarter view showing Waldeyer’s crests lying entirely on the occipital
orly projecting external occipital protuberance (Fig. 16).
The surface surrounding the external occipital protuberance exhibits a markedly rugose texture. The occipital
plane is shorter in length compared to the nuchal plane.
Likewise, the overall occipital breadth is wide, with the
lambdoidal suture exhibiting a low and broad pattern. The
lambdoidal suture runs between the asterionic borders
with a wormian bone at lambda interrupting it (Fig. 17).
Cranial Base
There is a well-developed and continuous median nuchal crest from inion to the remaining edge at opisthion.
On both sides of the crest, at its superior border, are
distinct scalloped regions that correspond to the attachment sites for mm. semispinalis capitis. Similarly, just
below the inferior nuchal line, two smaller scalloped regions indicate where mm. rectus capitis posterior minor
once attached. Lateral to those depressions, the surface
attachment areas of other nuchal muscles are less distinct
(i.e., mm. superior oblique). Two large distinct Waldeyer’s
crests of varying prominence lie entirely on the occipital,
paralleling the occipitomastoid sutures (Fig. 18). Medial to
the mastoid processes are distinct occipitomastoid crests;
the left is well developed and better preserved than the
right. Only the left posterior lateral border of the foramen
magnum near opisthion is present. This border exhibits a
distinct swelling of bone, which morphologically corresponds to a postcondylar tuberosity (see Weidenreich,
1951). From the remnant of the border, one can discern a
narrowing at the posterior region of the foramen magnum
just anterior to opisthion, which we refer to as the opisthionic recess.
The left mastoid process has better preserved outer
walls and presents a hollowed out cavity. The damaged
outer walls of the right mastoid process are flush with the
lateral aspect of the cranial vault. Both mastoid notches
are narrow and relatively short, with the left side more
deeply incised than the right. The notches open posteriorly into shallow and narrow digastric fossae. Anteriorly,
the left mastoid notch courses into the stylomastoid foramen whereas the right leads into a large excavation that
may be related to the jugular foramen. Both styloid processes are lacking and overall damage to the region has
obliterated that part of the tympanic forming the vaginal
process. An incomplete but discernable C-shaped foramen
spinosum is present on the remnant of the left sphenoid,
but due to erosion the right is poorly expressed. The damaged left carotid foramen faces posteriorly, but the posi-
SM 3 CALVARIA
Fig. 19.
axis.
363
An inferior view showing the squamotympanic fissure vector forming a 63.5° angle to the sagittal
tion of the right carotid is unclear due to poor preservation
of the region.
The anterior portion of the left mastoid is distinctly
separated from the tympanic plate by a prominent tympanomastoid fissure (sometimes referred to as the mastoid
fissure). At its widest breadth, the left tympanomastoid
fissure measures at least 6.1 mm, while the right side is
indiscernible due to the missing tympanic plate.
The anterior and posterior walls of the left mandibular
fossa parallel each other while the fossa is greater in
mediolateral width than in anteroposterior length. Of particular note is the squamotympanic fissure, sometimes
incorrectly referred to as the “Glaserian” fissure, which
runs the entire length of the floor in the deepest portion of
the fossa. The fissure forms an acute angle of 63.5° (i.e.,
mandibular fossa angle) to the sagittal axis and thus its
medial alignment is obliquely orientated (Fig. 19). The
well-preserved left fossa is relatively deep, measuring approximately 14 mm, and is constricted somewhat anteroposteriorly. The fossa is bounded anteriorly by a steep
pre-articular plane that opens onto a weakly developed
articular eminence. A relatively shallow gutter precedes
the eminence. The lateral edges of the mandibular fossae
do not extend beyond the cranial wall; instead, they are
positioned beneath and medial to the protruding suprameatal and supramastoid crests.
Cranial Sutures and Thickness
Having discussed the precautionary aspects of this subsection earlier, the ectocranial sutures of Sm 3 are uniform, weakly interdigitated, and mostly show lapsed
union. We follow here the classificatory groupings of sutures with their subdivisions from Cobb (1952) using the
schematic descriptions from Stewart (1954, see appendix
1). The ectocranial sutural interdigitation pattern of Sm 3
is illustrated in Figure 20. Of particular note is the superior border of the left squamosal suture which exhibits a
more horizontal rather than arc-like pattern (but see Holloway and Shapiro, 1992). The right squamosal suture is
not sufficiently preserved to determine its pattern. At
their posterior ends, the squamosal sutures form clear
mastoid angles of the parietal bone. The parietomastoid
suture is moderate in length and sweeps obliquely in a
posterosuperior direction. It measures 3.1 mm in length
on the left, and approximately 3.4 mm on the right.
Endocranially, both the right and left coronal sutures
are completely fused; the right is almost obliterated while
the left can be faintly detected. The sagittal and lambdoidal sutures are completely fused but not obliterated
whereas the squamosal sutures are completely obliterated. Likewise, the left and right sphenofrontal, sphenoparietal, and sphenosquamosal sutures are obliterated.
Fig. 20. The sutural interdigitation pattern of Sm 3. Polysiloxane
high-resolution dental impression material was used to mold the sutures
and all post-depositional cracks along the sutural borders. As seen in the
schematic drawing (see inset), the vinyl mold covered the area of the
sutures as they naturally exist in three-dimensional space. After remov-
ing the mold from the calvaria, it was sliced at bregma to allow the mold
to be laid out on a flat surface. This enabled the imprints of the sutures
and perisutural cracks to be accurately traced onto acetate paper, where
they are now depicted on a one-to-one scale in two dimensions.
Fig. 21. Midsagittal three-dimensional reconstruction shows the relatively high frontal and open occipital
angle. Note the relative thickness throughout the cranial vault. The middle meningeal vascular branching
pattern can also be appreciated.
SM 3 CALVARIA
365
Fig. 22. A three-dimensional CT reconstruction from an oblique posterior view showing the internal
morphology of the frontal crest.
The parietomastoid and occipitomastoid sutures are fused
and lie within slightly concave troughs that follow along
their sutural borders. Wormian bones can be seen at
lambda and at the junction of the right lambdoidal and
occipitomastoid sutures, the latter being unobservable ectocranially.
Overall, the calvaria exhibits a fairly thick roof and
walls (Fig. 21). The superior portions of the greater wing
of the sphenoid are thick and measure about 9 mm at their
superiormost border.
sella turcica, foramen ovale, foramen lacerum, and the
basiocciput is missing. Preserved portions of the sphenoid reveal the lateral wall of the foramen spinosum.
Most of the superior portion of the right petrosal revealing the internal acoustic meatus and approximately one
half of the left petrosal is preserved. Its damaged anterior portion exposes the superior carotid canal. The
superior surfaces of both petrosal portions of the temporal bone exhibit a weak arcuate eminence on the right
but absent on the left.
Anterior Endocranial Compartment
Posterior Endocranial Compartment
The anterior endocranial compartment lies largely
above the orbits, more so medially than laterally. Clear
and distinct anterior rami of the middle meningeal vessels
are present on both sides of the concave endocranial surfaces of the frontal squama. There is a sharp and welldeveloped frontal crest that is moderate in length and
tapers superoposteriorly (Fig. 22). The foramen cecum is
not present.
The right petrosal is well preserved, however, the posterior aspect of the left petrosal is somewhat eroded, obscuring morphological detail. The right petrous pyramid
acuminates apically throughout the length of its superior
surface. Its posterior surface reveals a narrow diagonal
channel that runs from the arcuate eminence towards the
jugular foramen below the internal acoustic meatus. It is
unclear whether this narrow groove is the remnant of a
sinus or simply an artifact resulting from taphonomical
processes. The aqueduct of the vestibule is present and
slightly roofed over. Although there is no subarcuate
fossa, the area of the petrous bone corresponding to the
Middle Endocranial Compartment
Most of the sphenoid bone forming the optic canals,
anterior and posterior clinoid processes, pituitary fossa,
366
MÁRQUEZ ET AL.
Fig. 23. A: Lateral view showing the left surface area of the Sm 3 endocast. Note temporal pole has been
reconstructed. B: Basal view of reconstructed endocast.
367
SM 3 CALVARIA
superior vestibular canal is marked by a slight depression.
The internal rims of both jugular fossae are missing or
damaged. The cruciform eminence prominently demarcates the moderately impressed cerebral and cerebellar
fossae.
Sinus Drainage System
The superior sagittal sinus is distinctly impressed only
from bregma to lambda. It divides into two slightly incised
transverse sinuses. The right transverse sinus flows into a
narrow and short sigmoid sinus, while the left flows into a
much wider but equally short sigmoid. Examination of the
endocast reveals a slightly impressed occipital sinus accompanied by a strongly expressed marginal sinus on the
right side that communicates with the right sigmoid before leading into the jugular foramen (see Endocast of
Sambungmacan 3 (Sm 3): A New Homo erectus From
Indonesia by Broadfield et al., this volume).
Middle Meningeal Vessels
The impressions of the middle meningeal vessels are
well developed on both sides of the calvaria. On each side
of the endocast, the main branch bifurcates as it courses
over the anterolateral wall of the temporal lobe. On the
calvaria, the anterior division of the main branch courses
upwards toward bregma with smaller bifurcations supplying the frontal region and the anterior portion of the
parietals. The posterior division of the main branch
courses posterolaterally where it soon bifurcates into
smaller side branches that supply the posterior region of
the parietals and the occipital region.
Endocast
An endocast was generated directly from the fossil. As
Figure 23 shows, the missing portions were reconstructed
in order to obtain an endocranial volume through water
displacement procedures (see Table 5 for results).
DISCUSSION AND EVOLUTIONARY
IMPLICATIONS
This preliminary study provides a basic description of
the newly recovered fossil hominid calvaria (Sm 3) from
Java, Indonesia. In general, the calvaria appears morphologically most similar to Homo erectus, depending of
course on one’s definition of that particular species. As
usual in human systematics, there are differences of opinion as to which characters are diagnostic of Homo erectus
(see Rightmire 1993; Stringer, 1984; Wood, 1984; 1991;
see also Hublin, 1986; Kennedy, 1991; Wolpoff, 1998), and
some authors would restrict this species to eastern Asia
(Tattersall, 1995). Additional studies have also detected
diversity within the Homo erectus group (e.g., Schwartz
and Tattersall, in press). In the context of the traits that
distinguish Indonesian Homo erectus from the Chinese
and African forms (Andrews, 1984; Rightmire, 1993;
Wood, 1991), the calvaria falls comformably within the
Indonesian spectrum. There are, however, a number of
traits that place the calvaria outside the classic definition
of H. erectus (sensu stricto). These include: an absent angular torus, a more open occipital/nuchal angle, a divided
supratoral sulcus, a more globular cranial vault, a vertically rising rather than a sharply receding frontal, and the
lack of a continuous bar-like occipital torus. The presence/
absence of these characters may be interpreted in several
ways: 1.) the combination of this group of characters in Sm
3 extends the known range of cranial variation of H.
erectus from Indonesia and China; 2.) this calvaria shows
evidence of evolutionary change within H. erectus; or 3.)
more than one species of Homo existed in the (presumed)
Middle Pleistocene of the Indonesian islands.
More exhaustive and comprehensive studies of this fossil calvaria and of variation within living populations will
undoubtedly allow us to better understand its taxonomy
and evolutionary significance. This is important; for, after
all, if one has not properly identified the actors, one cannot
possibly hope to understand the play.
ACKNOWLEDGMENTS
We thank Mr. H. Galiano for allowing us to examine the
specimen while it was in his care. We thank Drs. S.C.
Antón, T. Bromage, P.J. Gannon, R.L Holloway, J.T. Laitman, O. Pearson, E. Sarmiento, I Tattersall, and B. Wood
for their comments and suggestions. We also thank Dr. C.
Swisher III for his assistance with the geological provenience of the fossil. KM would like to thank Drs. S. Cachel
and M.E. Morbeck for their continued support. SM and
KM thank Ian Tattersall for his inspiration and tireless
assistance with this project.
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APPENDIX 1
Using the Todd and Lyon (1924) rating scale permits
the creation of a “closure formula,” thus allowing the scoring to act as a somewhat descriptive tool. Particular cranial landmarks further demarcate the three main sutures
of the vault (i.e., coronal, sagittal, and lambdoidal), which
enables a more detailed description of sutural classification. The descriptive categories of each suture are listed
below along with a schematic illustration showing suture
subdivisions and the stages of suture closure (Fig. A-1).
Stages of suture closure and sutural identification in the human skull.