The Spirit in Human Evolution - Waldorf Research Institute

and through its human plant pot, shattering the fossil into many small fragments. After
painstaking reconstruction by Alan Walker and Maeve Leakey, the skeleton gives a
remarkable image of an erectus boy who died between the ages of 11 and 12.
Typically, erectus had a fairly flat brow and forehead with large bony ridges about
the eye-sockets. The upper back of the skull was generally rounder than in Homo habilis,
through the lower back of the skull was often formed by an abrupt angle inwards giving
the skull a pointed shape in profile. Distinctive of the face shape was a prognathous lower
jaw with a chin sloping sharply back towards the throat.
Erectus brain size varied (based on endocasts and calculations from known
fossils) from 870 ccs (Sangiran, Java) to 1400 ccs (Verteszællos, Hungary). Only in the
sequence of fossils from Zhou-Kou-Tien (Peking Man) is there any evidence of an actual
increase in brain size over time, and that is slight. Brain shape, which is more relevant
than size to cognitive faculties, does show significant changes.
The recent discovery of an erectus fossil about 1 million years old in Ethiopia
has been claimed as evidence that there is in fact only one erectus species (reported in
Nature Science Update, March 20, 2002). The specimen, an almost complete skull minus
the lower part of the face, shares characteristics of both African and Asian forms. It opens
the possibility that skull shape within a species may vary according to factors other than
geographical location. Once more a fossil discovery comes along and complicates the
existing carefully constructed theories. Whether one or two species within the erectus
spectrum, the picture can only get more complex.
Fig 6.2 The Nariokotome Boy, KNM-WT. 15000. This partial
skeleton, reconstructed from hundreds of fragments, is the remains of
an immature African erectus, who probably died before he reached his
full adult height (from Shipman and Walker, 1996). The Nariokotome
Boy was estimated to have been about 164cm tall and weighed about
55kg. 6 He was not fully grown and although estimates vary on how
much more he would have grown (it is not totally clear if erectus had
the same developmental pattern as modern humans), as a grown man
he would probably have stood 6’ 1” tall and been powerfully built.
His physique is in fact not dissimilar to that of people living in the
area today. Close examination of the skeleton reveals some minor but
interesting differences from modern human anatomy, such as the
more bell-shaped rib cage, as opposed to the typically barrel shape of
modern chests. This observation reinforces the view that we became
progressively human from the lower limbs upwards. The proportions of
both arms and legs are more or less identical to our own. It also suggests
that the breathing apparatus was perhaps not yet fully opened to allow
the breath control necessary for full human speech.
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6
Walker, A. and R.E. Leakey, The Nariokotome Homo Erectus Skeleton, 1993.
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