-----------+---------+-------+------+-------+------
| | | | |
| | | | |
| | | | |
| | | | |
-----------+---------+-------+------+-------+------
| |Cranial| Mean|Height-| BN-
| | index|height|breadth| skull
| | | index| index|length
| | | | | index
| | | | |
South |Children | 84.4| 82.5| 89.6| 54
western | | | | |
and | | | | |
Midwestern | | | | |
Eskimo[160]|Adults | 79.3| 82.3| 93| 56
|(both | | | |
|sexes) | | | |
| | | | |
Nunivak |{Children| 79.5| 81.6| 92.5| 52.8
Island | | | | |
|{Adults | 75.6| 83.3| 96.7| 56
|(both | | | |
|sexes) | | | |
| | | | |
St. |{Children| 81.4| 84.1| 94.1| 54.5
Lawrence | | | | |
Island |{Adults | 77.3| 84.1| 96.5| 56.2
|(both | | | |
|sexes) | | | |
| | | | |
All |{Children| _81.8_|_82.7_| _92.1_|_53.8_
| | | | |
|{Adults | _77.4_|_83.2_| _95.4_|_56.1_
| | | | |
-----------+---------+-------+------+-------+------
-----------+------+-------+------+--------
| Percentage relation of
| dimensions of the vault in
|adults and children (adults =
| 100)
-----------+------+-------+------+--------
|Length|Breadth|Height| Basion-
| | | | nasion
| | | |diameter
| | | |
| | | |
South | | | |
western | | | |
and |} 90.1| 96.7| 93.2| 86.5
Midwestern | | | |
Eskimo[160]| | | |
| | | |
| | | |
| | | |
Nunivak | | | |
Island |} 91.7| 96.4| 92.3| 87.1
| | | |
| | | |
| | | |
| | | |
St. | | | |
Lawrence |} 90.2| 95.2| 93.2| 88.6
Island | | | |
| | | |
| | | |
| | | |
All | | | |
}|_90.8_| _96.1_|_92.9_| _87.4_
-----------+------+-------+------+--------
The main interest centers in the comparison of the relative proportions
of these skulls with those of the adults from the same localities.
These comparisons, given in the smaller table, are of considerable
interest.
The cranial index is considerably higher in the children. On analysis
this is found to be due almost wholly to a greater relative breadth
of the child's skull. During later growth the Eskimo cranium advances
materially more in length than in breadth. A further expansion in
breadth is evidently hindered by some factor outside of the bones
themselves, for nothing appears in these that could constitute such a
hindrance. And the only evident outside factor capable of producing
such an effect are the strong pads of the temporal muscles.
The mean height index (H × 100/(mean of L + B)) remains much the same
in the children and adults, indicating that the relative increase
during growth in skull length compensates for the lagging increase in
breadth, while the proportion of the height to the mean of the length
and breadth remains fairly stable.
The much greater growth in length than in breadth of the Eskimo skull
from childhood onward is shown even better in the second part of the
table by a direct comparison of the mean dimensions. The length of the
adult skull is by over 9 per cent, the breadth by less than 4 per cent,
greater than that in childhood in the same groups.
The adult Eskimo skull has also grown very perceptibly more in height
than in breadth, though somewhat less so than in length. The result is
a notably higher height-breadth index in the adult. Compared to that
in childhood the adult Eskimo skull is therefore relatively markedly
longer, higher, and narrower.
These facts are probably of more significance than might seem at first
glance; for it is precisely by the same characters, carried still
further, that some of the Eskimo differ from others. Let us compare
two of our largest and best groups, those of St. Lawrence Island and
Greenland:
---------------------+---------+--------+---------+---------
| Number | Skull | Breadth | Height
|of skulls| length | |
| (both | | |
| sexes) | | |
---------------------+---------+--------+---------+---------
St. Lawrence Island | (293) | 18.05 | 13.90 | 13.45
Greenland | (101) | 18.51 | 13.30 | 13.54
---------------------+---------+--------+---------+---------
The Greenland skull is longer, narrower, and somewhat higher. The
differences are less than those between a child and an adult western
Eskimo, but of the same nature. This apparently speaks strongly for
the development of the Greenland type of Eskimo cranium from the
western. On the other hand, the type of skull shown by the Eskimo child
approaches much more closely than that of the Eskimo adult to the type
of the skull of the Mongol.
The above are mere observations, not theories, and they carry a strong
indication that mostly we are still floundering only on the borders of
true anthropology, embracing all phases of life and development, which,
if mastered, would give us with beautiful definition many now vainly
sought or barely glimpsed solutions.
A highly interesting feature is the relatively great development in the
Eskimo, between childhood and the adult stage, of the anterior half of
the skull or basion-nasion dimension. This augments, it is seen, by
even 3.4 per cent more than the length. This growth must involve some
additional factor to those inherent in the bones themselves and in the
attached musculature, and this can only be, it seems, the development
of the anterior half of the brain. Evidently this portion of the brain
between childhood and adult life grows in the Eskimo more rapidly than
that behind the vertical plane corresponding to the basion. It is a
very suggestive condition calling for further study, and thus far
almost entirely wanting in comparative data on other human as well as
subhuman groups.