Capítulo 4. Instituciones (centros de gobierno)
4.3. Gestión estratégica y monitoreo
incisor lengths also show Aborigines to tend to fall at one extreme but with less clear s e paration from other groups
(table 4-14). Melanesians especially West Nakanai are 2
somewhat exceptional for P (table 4-17) due to their
2
reduced P length (see later). Amerindians are far more distinct from Aborigines for third molar length than second molar length; Aleuts fall wit h i n the Aboriginal range except for C. The same tendency, but less marked, is also
apparent for lower posterior molar lengths (tables 4-19 to 4-23) .
Thus the shape of the Aboriginal den t i t i o n can be summarised by large posterior molars: second molars (which are less variable than third molars) show this trend more unequivocally, and upper molars show this trend more
clearly than lower molars. The mesiodistal data could be interpreted as the result of the greater interproximal wear that Aborigines tend to experience, either because
interproximal wear may tend to be more pronounced on the anterior six teeth, or because second molars experience interproximal wear posteriorly only after the third molar has erupted, and third molars experience it only anteriorly. This may well be true to some degree, as shown by the
tendency for Murray Valley to be extreme amongst Aborigines for the mesiodistal indices. However the agreement between length and breadth data suggests that, even if interproximal wear is playing some role, Aborigines' posterior molars as
they erupt in the d e n t ition tend to be large compared to the more anterior teeth, no doubt to maximise the grinding surfaces
available for m a s t ication of a demanding diet. The fact that Amerindians (mostly h u nter-gatherer or hunter-gatherer/ horticulture mixed economy groups) share this trait to some degree, and that Aleuts tend to share it for lengths and
for breadths relative to premolar breadths, supports this view. The high rate of third molar agenesis amongst Eskimos
(Brothwell et al 1963:184,186) is at first sight puzzling. It may be that the tendency for the germs to develop as large structures actually causes their frequent agenesis in cases of insufficient room in the developing jaws, given their only moderate rate of interstitial wear.
I l l . By contrast east Asians and Melanesians (West Nakanai are to a large degree exceptional) appear to have undergone a reduction, both absolutely and relatively, in the size of their posterior molars, possibly reflecting their long acquaintance with a predominantly horticultural economy and decreasing mastication stresses on the
dentition. It is also clear that Melanesians, despite their
3
higher M hypocone expression (chapter 3, section 1), tend to have relatively smaller maxillary third molars
than southeast Asians (tables 4-3 to 4-8, 4-14 to 4-18).
Considering Melanesians, great variability in the ranges for the various indices becomes apparent. One
trend however appears to separate them from other races - shortening of the upper second premolar accompanied by some lengthening of the upper first molar. This can be expressed by either upper second premolar robusticity (table 4-24) or upper second premolar length cf. upper first molar length
(table 4-17). Comparing upper and lower second premolar lengths and upper and lower first molar lengths (table 4-25)
2
we observe that the Melanesian P tends to be short c f . P~
1 z
and M tends to be long cf. suggesting that their second premolar shortening/first molar lengthening is a feature
specifically of the upper dentition (see also tables 4-22 and 4-24) .
A very special form of interstitial wear would have to be invoked to account for this trend - one where (compared to other races) the Melanesians' upper second premolar
experiences quite extensive interstitial wear, but the upper first molar (against which the upper second premolar wears) is not shortened but if anything relatively l e n g t h e n e d. Such a process of interstitial wear would occur only on the upper dentition; and would be distinctive for a minimum of seven Melanesian groups but not found elsewhere. Clearly we are dealing with an odontometric trend which is not simply the result of post-eruption wear. It may be hypothesised that Melanesians' second upper premolars tend to erupt in the
dentition relatively reduced and upper first molars relatively increased in length, as though the two tendencies compensated
for each other. Subsequent interstitial wear may well exaggerate these trends, making an upper second premolar of reduced
length appear even more so.
The single Melanesian group which departs from this pattern is the Biakers (tables 4-17 and 4-24), who live just east of the Vogelkop and so can be expected to be in the clinal region between the southeast Asian and Melanesian patterns.
A number of trends appear to distinguish
Austromelanesians from east Asians as a whole. Austromelanesians appear to have short upper premolars, especially the second,
relative to the summed molar length (tables 4-16 and 4-17, last column) - Melanesians because of some M^ lengthening
2 3
and Australian Aborigines because of M and M lengthening. Austromelanesians are also characterised by more robust premolars (table 4-24). Australian Aborigines show robust premolars in both the upper and lower tooth row and much
of this may well be due to higher levels of interstitial wear, especially as Murray Valley are extreme in this regard.
Melanesians on the other hand have upper premolars (especially
2
P ) ranging from very narrow to narrow, but lower premolars ranging from narrow to broad, so they appear to enjoy a genetically based increase specifically in upper premolar robusticity.
There also appears to be a cline in upper posterior molar breadths relative to lower posterior molar breadths, especially for the second molars. Australian Aborigines at one end are characterised by the broadest upper molars, and northeast Asians and Amerindians at the other end are characterised by the broadest lower molars (table 4-26).
Within the Orient-Pacific this cline corresponds to the Australia to northeast Asia cline of increasing hypocone reduction, so
possibly these two traits are linked.
The above differences between Melanesian and east Asian odontometrics are summarised in a Penrose shape analysis
113
of those diameters measuring upper premolar robusticity
1 2
(P and P M-D and B-L); and upper second premolar
2 1
shortening/first molar lengthening (P M-D, M M-D, M^ M-D). Reasons for choosing specific comparative groups and details of the analysis are given in Appendix D, section 2 (table D-7); results are graphed using
multidimensional scaling in fig. 4-1. Melanesians especially Goroka/Lufa and Nasioi fall at one extreme and east Asians fall at the other in a fairly tight cluster. New Britain Tolai (Wolpoff) show the least emphatically Melanesian pattern of the Melanesian groups, and Batavians evince the most Melanesian-like odontometry of the east Asian groups. Axis 2 suggests a cline from mainland east Asia/
northeast Indonesia, through Java and Austronesian- speaking Melanesians, to the Papuan-speaking New Guinea Highlanders.
Considering southeast Asians three features become apparent - long upper premolars, narrow lower incisors, and lower incisors of about equal width. Long upper premolars cf. their breadths or summed upper molar length has already been discussed as a general east Asian tendency; Indonesians, including LB peripherally, also affect long upper premolars relative to upper incisor width which appears to be a local
'specialisation' (table 4-27). Mainland east Asians,
including Thais, Bhutanese and Ainu, do not show this pattern. The interpretation is complex but Melanesians have been
argued to have short upper premolars, and northeast Asians, relative to southeast Asians, tend to have wide incisors relative to posterior molar length (tables 4-14 and 4-19).
Narrow lower incisors especially the lateral are characteristic of Amerindians even moreso than southeast Asians, and this can be seen both in absolute dimensions
(table 4-3) and in relation to upper incisor breadths (table 4-26). This is one trait that LB appears not to share with other southeast Asians, but LB lower incisors are poorly sampled so inadequate sampling may be responsible for this discrepancy.
1^ shows a tendency to be nearly as wide as I2
in southeast Asians, including LB, compared to other races, with only Batavians falling within the ranges of other
races (table 4-28). This tendency could be an artefact of interstitial wear or even occlusal wear, or could reflect slight differences in the mode of lower incisor eruption sequence or the available room in the jaw for the developing teeth.
The southeast Asian odontometric trends are not nearly as unambiguous as the Melanesian and Australian
Aboriginal trends discussed before. This can be seen either from the relevant tables, fig. 4-2# or the details of shape distances in Appendix D. Tolai (Wolpoff) for instance share the southeast Asian pattern for upper incisor widths
1 2 1 1
c f . upper premolar lengths (I , I , P , P M-D) and upper incisor breadths cf. lower incisor breadths (I, , I„ , i \
2 1 z
I B-L). Batavians are similar to Melanesians for lower incisor relative widths (1^, M-D). South Chinese are similar to at least some southeast Asian groups for lower incisor relative widths, and upper incisor widths cf. upper premolar lengths.
Applying the Penrose shape statistic to the above three sets of variables for the same populations used before
(details in tabled D-8 and D-9), adding the distances and plotting the final inter-group distances using
multidimensional scaling, we arrive at the interrelationships suggested in fig. 4.2. As suggested for upper incisor cf. upper premolar lengths, the southeast Asian can more properly be called the Indonesian pattern, with four Indonesian groups forming a fairly tight cluster and LB falling peripheral
to this cluster. South Chinese, Tolai (Wolpoff) and Thais are also fairly close to the Indonesian cluster, while the Melanesian groups Nasioi and New Guinea Highlanders are the furthest removed. The Indonesian trends, though
individually not particularly diagnostic, work together as a statistical complex to give reasonable discrimination between Indonesian and non-Indonesian groups. Indeed the graphed results may be thus interpreted, that as we move
away from central Indonesia, so the odontometric pattern becomes decreasingly Indonesian.
115 .
Considering northeast Asians cf. other races, we find a general tendency for incisor breadths to be as
large or larger relative to premolar and molar breadths, both for the upper and lower dentition (tables 4-4, 4-5, 4-9, 4-10, 4-29). Northeast Asians achieve good
separation from Melanesians for I"*' and to a lesser extent
2
I (tables 4-4, 4-5, 4-29) but poor separation for the lower incisors. For the lower incisors particularly I rather they achieve good separation from southeast Asians and Amerindians (tables 4-9 and 4-10), reflecting the
reduction in lower incisor breadths of the latter two races (table 4-26). There may also be some faint tendency for the incisors to be long relative to the posterior molars
especially (tables 4-14 and 4-19), but this is only unambiguous in comparison to Australian Aborigines.
Table 4-3 suggests the principal general differences between the northeast Asian and the southeast Asian
dentition: anterior tooth dimensions show more or less equivalent ranges, but southeast Asians are clearly larger for posterior tooth dimensions, usually with non-overlapping ranges of means. Lower cheek teeth breadths are the
exception that proves the rule, for while lower cheek teeth breadths are of equivalent size, southeast Asians' lower incisor breadths are specifically reduced.
Applying the statistical technique used above to
1 2 1
upper incisor breadths c f. upper molar breadths (I , I , M ,
2 3 1 2 1 2
M , M B-L) and c f. upper premolar breadths (I , I , P , P B-L), and the same procedure for the lower dentition (details in tables D-10 and D-ll), we arrive at the configuration of groups given in fig. 4-3. A useful by-product of this analysis, one not obvious from the bivariate analysis, is the tight
clustering of southeast Asian groups that results (fig. 4-3, tables D-10 and D-ll), suggesting that southeast Asians tend to a fairly uniform buccolingual shape of the dentition comparing incisors and cheek teeth. A loose association is suggested between the Chinese groups and the Melanesian groups Nasioi and Goroka/Lufa, but at the same time Tolai (Wolpoff)
lie at the opposite pole, falling close to the southeast
Asian cluster. This underlines the variability of Melanesian
odontometrics. Odontometric variability, observable in
terms of both size and shape, parallels Melanesians'
variability for a large number of somatic features (Howells 19 73b:161,163), reflecting their sub-division into
numerous breeding isolates many of which have considerable time depth (Howells 1973b:166).
Coon's (1962:352) assertion that Mongoloids have relatively large anterior teeth, and Australoids relatively
large cheek teeth, requires some qualification. Northeast
Asians do have relatively large incisors, at least
regarding breadths, but this trait is not true of southeast
Asians and Amerindians. Australian Aborigines do have
relatively large molars, particularly the posterior upper molars, but for Melanesians, particularly the more
"Australoid" Melanesians, this is true only of upper first molar length and seems to occur at the expense of upper
second premolar length. Considering the Orient-Pacific we move from large posterior molars (Aborigines) to a somewhat lengthened
upper first molar (Melanesians), to long upper premolars
(southeast Asians), to possibly wide but certainly broad incisors (northeast Asians), as though reduction in upper tooth size were moving in a uniform direction from the most posterior teeth anteriad.
To summarise these trends, all shape distances obtained from the previous statistical tests are summed and the resultant matrix graphed using multidimensional scaling, to produce the arrangement in fig. 4-4. Southeast Asians form a fairly tight cluster, with south Chinese and north
Chinese diverging from the southeast Asian cluster in one direction, and Melanesians diverging in a different direction.
Essentially the same relationships are suggested when all dimensions are put into a Penrose shape statistical analysis and the resulting distances graphed (fig. 4-5 and
table D-12). Indeed it was found during experimentation
that, so long as a large number of dimensions are included, any set of dimensions would suggest the same relationship
(e.g. figs 4-6 and 4-7). The strong tendency for southeast Asian groups to cluster together whether we are considering Melanesian, Indonesian, or northeast Asian trends has
already been noted, and they clearly show a marked uniformity in the shape of the total dentition, as can be seen from
the generally tight ranges for southeast Asians' mean tooth diameters (table 4-3) and tooth size indices (tables 4-4 to 4-29).
A Penrose shape test using only buccolingual
measures (fig. 4-6, table D-12) suggests essentially the same relationships as suggested in figs 4-4 and 4-5, though here Gilimanuk are spun off from other southeast Asians to some degree. This can be considered confirmation that
interstitial wear is not significantly affecting contrasts based on mesiodistal measures between Melanesians and east Asians, none of whom are suspected to have experienced marked interstitial wear (table 4-1). Considering figs 4-1 to 4-6 there is a consistent suggestion that south Chinese are closer to the southeast Asian odontometric cluster than are north Chinese, and frequently Thais adopt an intermediate position between Indonesians and south Chinese. The probable inclusion of some recent south Chinese immigrants in the
Batavian and Surabayan samples (chapter 2, section 1) appears to have had negligible effect, since Batavians and Surabayans consistently cluster with Early Metal Period groups where such direct south Chinese admixture is unlikely. Melanesians show
a variable odontometric pattern, Tolai (Wolpoff) consistently falling closer to southeast Asians especially Batavians, and Nasioi and Goroka/Lufa Highlanders either standing apart
or tending to fall relatively close to northeast Asians. Only in the positioning of the pre-Metal Period groups Flores and Guar Kepah do the above graphs radically disagree - a point to be discussed in the next section.
117 .
The present analysis, while not intended to be a comprehensive survey of Amerindian odontometrics, does
establish that they probably represent a distinct complex. For instance Amerindians share the reduced lower incisor
2
breadths of south Asians, the broad P of Mongoloids generally (table 6-24) despite their higher interstitial wear, and the broad lower molars of Aborigines. In
addition Harris and Nweeia (1980:86) argue that Amerindians are distinguished from non-Amerindians by having an 1^ and
2
I relatively equal in length, but an 1^ and I9 more different in length. These claims are more or less substantiated by the present analysis (table 4-28) and are exemplified by Aleuts whom Harris and Nweeia classify as Amerindian; however some Melanesians fall comfortably within the Amerindian range for both indices, e.g. Nasioi
and Janzer's Tolai sample, and Aborigines show an equivalent tendency for I2 length to be considerably larger than 1^ length (table 4-28).
It remains briefly to discuss a number of other groups. Aleuts show long second and third molars, and broad molars cf. premolar breadth, for which traits they are unlike east Asians and similar to Aborigines. East Greenland
Eskimos also show long second and third molars c f . first molar length. Aleuts depart from the Aboriginal pattern
as they show large canines relative to their molars (table 4-6, 4-11, 4-15).
On the limited data available (table 4-1 ) Ainu
2 1
appear to have a relatively low P /M M-D index (table 4-17) and a short upper second molar relative to upper incisor, canine and first molar lengths (tables 4-14, 4-15, and 4-18), all of which distinguish them from east Asians generally.
2 1
One hesitates before suggesting that their low P /M M-D
index and high M^/M^ M-D index indicate a Melanesian affinity. Their teeth are smaller than recent Japanese (Hanihara 1977b: 414). The Ainu are intriguing in their odontometrics and fuller data might prove revealing.
Bhutanese diverge from the more usual east Asian dental shape by having short and narrow premolars (tables 4-7, 4-8, 4-20, 4-21, 4-24 and 4-27), a short second molar
119 .
(tables 4-14, 4-15, 4-18, 4-19 and 4-20),and low canine buccolingual diameters (tables 4-6 and 4-11) even though they are an all-male sample. Whether these differences reflect a trend towards south Asian odontometrics is beyond the scope of the present study, but Bhutanese clearly diverge from the main Oriental-Pacific patterns.
On the data available, Mokapu Hawaiians would appear to have non-Mongoloid, Melanesian (?) odontometrics. The upper first molar is long relative to upper first
premolar and lower first molar length (tables 4-16 and 4-25), and the first premolars are robust (table 4-24) which
would not appear to be due to interstitial wear (table 4-1). Mokapu further diverge from the southeast Asian pattern
by showing a narrow upper medial incisor relative to lower medial incisor breadth (table 4-26), and the relative proportions of the lower incisor widths are also more
Melanesian than southeast Asian (table 4-28). Though it is impossible to test Mokapu for most of the specific racial odontometric trends, the available measurements may be
submitted to a Penrose shape analysis (table D-13, fig.4-7). Southeast Asian groups form a fairly tight cluster; and
very distant from them, and clustering to some degree with Melanesian groups,are the Mokapu. Thus although Mokapu may have Sundadont dental morphology, their odontometrics are very different from southeast Asians and instead have a Melanesian flavour.
Summary
Odontometric analysis suggests a number of geographically definable complexes in the circum-Pacific region: the Aboriginal pattern characterised by large posterior molars; the Melanesian pattern (east of Irian