Relative Variation in Human Proximal - Holliday

[djoser-xyyman]

Body Proportions of Circumpolar Peoples as Evidenced
From Skeletal Data: Ipiutak and Tigara (Point Hope)
Versus Kodiak Island Inuit
Trenton W. Holliday1* and Charles E. Hilton2
1Department of Anthropology, Tulane University, New Orleans, LA 70118
2Department of Anthropology, Grinnell College, Grinnell, IA 50112-1690
KEY WORDS Bergmann’s rule; Allen’s rule; ecogeographical patterning; cold adaptation
ABSTRACT Given the well-documented fact that
human body proportions covary with climate (presumably
due to the action of selection), one would expect that the
Ipiutak and Tigara Inuit samples from Point Hope,
Alaska, would be characterized by an extremely coldadapted
body shape. Comparison of the Point Hope Inuit
samples to a large (n > 900) sample of European and European-
derived, African and African-derived, and Native
American skeletons (including Koniag Inuit from Kodiak
Island, Alaska) confirms that the Point Hope Inuit evince
a cold-adapted body form, but analyses also reveal some
unexpected results. For example, one might suspect that
the Point Hope samples would show a more cold-adapted
body form than the Koniag, given their more extreme
environment, but this is not the case. Additionally, univariate
analyses seldom show the Inuit samples to be
more cold-adapted in body shape than Europeans, and
multivariate cluster analyses that include a myriad of
body shape variables such as femoral head diameter, biiliac
breadth, and limb segment lengths fail to effectively
separate the Inuit samples from Europeans. In fact, in
terms of body shape, the European and the Inuit samples
tend to be cold-adapted and tend to be separated in multivariate
space from the more tropically adapted Africans,
especially those groups from south of the Sahara. Am J
Phys Anthropol 142:287–302, 2010. VVC 2009 Wiley-Liss, Inc.

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[djoser-xyyman]

Relative Variation in Human Proximal and Distal Limb
Segment Lengths
Trenton W. Holliday1* and Christopher B. Ruff2
1Department of Anthropology, Tulane University, New Orleans, Louisiana 70118
2Department of Cell Biology and Anatomy, Johns Hopkins University Medical School, Baltimore, Maryland 21205
KEY WORDS limb proportions; allometry; variance-covariance matrices
ABSTRACT The pattern of variation and covariation
of proximal and distal limb segment lengths was examined
within and between 20 geographically diverse skeletal
samples of modern humans. Analyses of variance-covariance
matrices (VCMs) of logarithmically transformed
(ln) variates of humerus, radius, femur, and tibia length
were performed to test the following hypotheses: first,
within populations, the distal and proximal segments will
have equal relative (i.e., size-independent) variability.
However, between populations, the tibia is predicted to be
more variable than the other segments. Tests of fit of
computed VCMs to theoretical matrices by an iterative
procedure (Anderson [1973] Ann. Stat. 1:135–141) reject
the equal variance hypotheses, rather suggesting that the
relative variances of the distal limb segments are greater
than are those of the proximal. Males and females differ
somewhat in that within females, the distal segments of
both limbs have equal variance, while within males, the
tibia has greater relative variance than the radius. The
second hypothesis, regarding between-group variability, is
somewhat supported in that between human populations,
one cannot reject that the tibia has greater relative
variance than the other limb segments. However, neither
can one reject an alternative hypothesis that both
distal limb segments (tibia and radius) are more variable
than the proximal segments. Differential growth
allometry is explored, and likely plays a major role in
differences seen both within and between human populations.
Am J Phys Anthropol 116:26 –33, 2001.
© 2001 Wiley-Liss, Inc

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[djoser-xyyman]

One of the few interesting threads. So I will post.

What I got from the study is Europeans and other cold adapted peoples show similar traits.
1. Thick/long trunks
2. Short legs and arms
3. Large femoral indices
4. Broad hips(and flat butt). That why I can’t find a good pair of fitting jeans. LOL!
5. Hairy body
What was the nonsense Gigantic was talking about “gracile” Europeans.



---------
From. . .

Body Proportions of Circumpolar Peoples as Evidenced
From Skeletal Data: Ipiutak and Tigara (Point Hope)
Versus Kodiak Island Inuit
Trenton W. Holliday1* and Charles E. Hilton2
1Department of Anthropology, Tulane University, New Orleans, LA 70118
2Department of Anthropology, Grinnell College, Grinnell, IA 50112-1690


Rather, all high-latitude groups, including Europeans,
evince a more cold-adapted physique, and only for
a few key traits (e.g., relative bi-iliac breadth, female relative
femoral head size) are the circumpolar groups consistently
significantly more cold-adapted than Europeans.
Thus, the major contrast in body shape is found
between Europeans and circumpolar groups on the one
hand, and tropical and, to a lesser extent, subtropical,
Africans on the other.[/b] This is an [/b]unexpected finding [/b]in
that it hints that[/b] Europeans likely experienced (and perhaps
still experience today) significant selection for a
‘‘cold-adapted’’ postcranial morphology.[/b]



ABSTRACT Given the well-documented fact that
human body proportions covary with climate (presumably
due to the action of selection), one would expect that the
Ipiutak and Tigara Inuit samples from Point Hope,
Alaska, would be characterized by an extremely coldadapted
body shape. Comparison of the Point Hope Inuit
samples to a large (n > 900) sample of European and European-
derived, African and African-derived, and Native
American skeletons (including Koniag Inuit from Kodiak
Island, Alaska) confirms that the Point Hope Inuit evince
a cold-adapted body form, but analyses also reveal some
unexpected results. For example, one might suspect that
the Point Hope samples would show a more cold-adapted
===
body form than the Koniag, given their more extreme
environment, but this is not the case. Additionally, univariate
analyses seldom show the Inuit samples to be
more cold-adapted in body shape than Europeans, and
multivariate cluster analyses that include a myriad of
body shape variables such as femoral head diameter, biiliac
breadth, and limb segment lengths fail to effectively
separate the Inuit samples from Europeans. In fact, in
terms of body shape, the European and the Inuit samples
tend to be cold-adapted and tend to be separated in multivariate
space from the more tropically adapted Africans,
especially those groups from south of the Sahara.[/b] Am J
Phys Anthropol 142:287–302, 2010. V

===


Archeological/artifactual evidence suggests that foragers
in both periods exploited sea mammals (ocean currents
keep much of the coastal water ice-free throughout
the winter). However, during the Ipiutak Period, there
was far more emphasis on caribou hunting, while during
the later Tigara Period, hunters made much more frequent
use of whales (Larsen and Rainey, 1948)—

===
Body proportions of humans [and other endothermic
(i.e., ‘‘warm-blooded’’) species] have long been known to
show significant correlations with climatic variables and
their proxies.

====
Specifically, two empirically derived ecogeographical
rules, those of Bergmann (1847) and Allen
(1877), state that within a widespread endothermic species,
those in colder regions will tend to weigh more
(Bergmann’s rule) and be characterized by shorter
appendages (Allen’s rule) than their conspecifics in
warmer climes.


===
In particular, it has long been recognized
that circumpolar peoples (e.g., Inuit, Aleuts, Sa´mi) have
more foreshortened limb segments and broader trunks
and are heavier on average than populations at even the
mid-latitudes (Trinkaus, 1981; Ruff, 1994; Holliday,
1997b).

===
Note that while within each
region, males tend to have higher indices than females;
across regions, the Africans tend to have low index values
and the circumpolar groups have high index values,
with the Europeans appearing to be somewhat intermediate.


===


Likewise, the North and Sub-
Saharan African females are not significantly different
from each other, but are different from all other groups European females are significantly different from all
other groups, with significantly lower index values than
the circumpolar groups and larger values than the African
samples. Likewise, the European males have significantly
smaller femoral heads than the Tigara and significantly
larger femoral heads than the Africans.


===


Two other indices studied are the brachial (radius
length:humerus length) and crural (tibial length:femoral
length) indices. These indices assess the length of the
distal limb segment relative to its proximal counterpart
within each limb and have long been known to exhibit a
significant relationship with climatic variables, with
groups from colder climes evincing lower ratios (Coon,
1962; Badoux, 1965; Trinkaus, 1981). This seems to be
due to the fact that the length of the distal limb segment
is more developmentally labile than the proximal segment
(Jantz and Jantz, 1999; Holliday and Ruff, 2001).

===
As expected, the African
groups have high brachial indices, while the European
and circumpolar groups are characterized by lower indices.

===


Box plots for the limb length:skeletal trunk height
ratios are found in Figure 3A–D. All limb:trunk indices
show an apparent clinal distribution, with European and
circumpolar samples characterized by lower indices,
while the Africans show higher index values.

===

Note that the Nubians used in this study are
thought by some to represent an immigrant population
from Europe or Western Asia [see Holliday (1995)].

=====

Arctic Circle, we would find
that they exhibit among the most extreme human body
shapes in the world—i.e., they would be characterized by
the most foreshortened limbs, the broadest pelves, and
highest femoral head to femoral length ratios of all the
groups sampled.

====


The results of our study are somewhat mixed with
regard to these hypotheses. As was found by Ruff (1994,
2002), contrasts between the circumpolar groups and
Africans are consistently significant, with Ipiutak and
Tigara males and females significantly different from the
Sub-Saharan Africans for every calculated index, the
Koniag different from the Sub-Saharan Africans for most
indices, and all three circumpolar groups showing significant
differences from the North Africans for a plurality,
if not majority of the indices calculated. Contrasts
between the circumpolar groups and the Europeans,
however, are decidedly less marked.

===

The environmental component of body proportions has
been noted for some time in experimental studies (e.g.,
Lee et al., 1969; Weaver and Ingram, 1969; Riesenfeld,
1973) in which animals raised in different climate-controlled
environments ultimately developed different body
proportions, with animals raised in the cold evincing
shorter limbs than their conspecifics (or litter mates)
raised in hot environments.

==


To make matters more complicated, climate is not the
only factor that can act on body proportions—malnutrition
is documented to lead to reduced stature, which
tends to be associated with lower limb:trunk proportions
and foreshortened distal limb segments (Tanner et al.,
1982; Jantz and Jantz, 1999).

==

Specifically, the earliest
modern humans in Europe for whom we have body
proportion data tend to show more African-like body proportions
(Holliday, 1997a), while later European modern
humans show foreshortened limbs in spite of archeological
data indicative of improved cultural buffering. This
suggests selection for shorter limbs in Late Pleistocene
Europe, although we also cannot as of yet rule out the
possibility that late Pleistocene gene flow from Neandertals
to early modern Europeans played some role in
establishing more ‘‘cold-adapted’’ limb proportions for
this latter population (Holliday, 1997a, 2006b).


===

and it is even more
surprising that these three circumpolar groups exhibit
so few body proportion differences from Europeans.