It
is apparent that the many European representatives of Homo
heidelbergensis possessed features that presupposed the
Neanderthals. The Hominin population of Europe was becoming increasingly
Neanderthal-like during the course of the Middle Pleistocene (Arsuaga
et al., 1993; Smith et al. 1989; Tattersall, 1999; Rightmire,
1998, 2001). The Accretion model of Neanderthal evolution attempts
to place a loose definition on this transition. This model comprises
four stages that build up to the final cranial features associated
with the ‘Classic’ Neanderthals. According to Dean
et al. (1998), the earliest stage contains ‘early-pre-Neanderthals’
that including Petralona and Arago. The second stage of the Accretion
Model includes ‘pre-Neanderthals’ specimens such as
Reilingen, Steinheim, Swanscombe and the finds from the Sima de
los Huesos. This group shows the beginnings of the double-arched
browridges and mid-facial prognathism. The third stage contains
‘early Neanderthals’ specimens from Ehringsdorf, Saccopastore,
Krapina and some of the Shanidar specimens. This stage includes
the appearance of the occipital bun. The final stage represents
the ‘classical Neanderthals’ with traits such as increased
mid-facial prognathism and a deepened orbital sulcus. This last
group includes Feldhofer 1, Gibraltar 1 (Forbes Quarry), La Chapelle-aux-saints,
La Ferrassie, Amud and the other specimens form Shanidar.
The Accretion Model assists with defining the appearance of the
Neanderthal-like characters in European Hominins. This model is
a basis for assessing an evolving lineage leading from one discrete
species to another (Ferdinando and Lynn, 2004). Even with four
distinct stages, it would appear to me quite easy to retain a
simple two species assignment within this model. The majority
of the specimens assigned to the two earliest stages are clearly
representatives of the previously described G. Phillip Rightmire’s
characterization of Homo heidelbergensis. Specimens allocated
to the latter two stages are members of Homo neanderthalensis.
This assessment is tenable even if the members of stage three
do not posses every single feature seen in the ‘Classic’
Neanderthals.
I would like to suggest a few minor changes to this model (Ferdinando
2004). First, the distinction between stage 1 and 2 could be utilized
to define Homo heidelbergensis specimens that do not
possess and do present the Neanderthal morphology, respectively.
An informal distinction between stage 2 and 3 can be to review
the proportion of Neanderthal vs. non-Neanderthal features present.
If the number of Neanderthal traits is over 50% this specimen
probably belongs in stage 3. Finally, I assert the need for another
stage in this model that of stage 5 ‘progressive’
Neanderthals. Reduction of certain Neanderthal traits in Saint-Cesaire
and Vindija could represent a new direction for Neanderthal evolution,
or gene flow with incoming moderns (Malez et al., 1980; Smith
et al., 1985; Frayer et al., 1993). The elements that are affected
include reduced and modern-like separated browridges, smaller
nasal openings, slight development of chins, shortened retromolar
spaces and a more anterior placement of the mental foramen.
| Stage |
Species |
Examples |
Traits |
1 |
H.
heidelbergensis |
Atapuerca
4, Mauer |
No Neanderthal
Traits |
2
|
H.
heidelbergensis |
Arago,
Petralona, Steinheim, Swanscombe,
Atapuerca 5, Reilingen |
Can possess
many Neanderthal traits, but not the complete suite |
3 |
H.
neanderthalensis |
Saccopastore,
Biache-Saint Vaast, Krapina, Shanidar (early) |
Should
display a large range of Neanderthal traits |
4 |
H.
neanderthalensis |
Feldhofer,
La Chapelle, Gibraltar, Shanidar (late), Amud |
Have the
characteristic ‘Classic’ morphology |
5 |
H.
neanderthalensis |
Saint-Cesaire,
Vindija |
Some feature
may be ‘progressive’ towards a modern morphology |
This
list is an adaptation of the four stage Accretion Model from Dean
et al. (1998).
The assignment of these specimens to ‘stages’ is not
meant to convey chronological information. There is considerable
temporal overlap between the various stages. The stages are of
importance to track the representation of Neanderthal features
(which does have a quasi-temporal flow).
Works
Cited
Arguaga,
Juan-Luis., Martinez, Ignacio., Gracia, Ana., Carretero, Jose-Miguel.
and Carbonell, Eudald. (1993). Three New Human Skulls from
the Sima de los Huesos Middle Pleistocene Site in Sierra de Atapuerca,
Spain. From Nature. V362: 534-537.
Dean,
David., Hublin, Jean-Jacques., Holloway, Ralph. and Ziegler, Reinhard.
(1998). On the Phylogenetic Position of the Pre-Neanderthal
Specimen from Reilingen, Germany. From Journal of Human Evolution.
34: 485-508.
Ferdinando,
Peter, and Lynn, Misti. (2004). Evolution
in a Hominin Lineage: The Appearance of the “Classic”
Neanderthal Morphology (abstract). From Journal of Morphology.
V260(3): 290.
Ferdinando,
Peter. (2004). Evolution in a Hominin Lineage: The Appearance
of the “Classic” Neanderthal Morphology (presentation).
At the 7th International Congress of Vertebrate Morphology, 27
July-1 August..
Frayer,
David W., Wolpoff, Milford H., Thorne, Alan G., Smith, Fred H.
and Pope, Geoffrey G. (1993). Theories of Modern Human Origins:
The Paleontological Test. From American Anthropologist. 95:
14-50.
Malez,
Mirko., Smith Fred H., Radovcic, Jakov. and Rukavina, Darko. (1980).
Upper Pleistocene Hominids From Vindija, Croatia, Yugoslavia.
From Current Anthropology. V21(3): 365-367.
Rightmire,
G. Philip. (1998). Human Evolution in the Middle Pleistocene:
The Role of Homo heidelbergensis. From Evolutionary Anthropology.
6: 218-227.
Rightmire,
G. Philip. (2001). Patterns of Hominid Evolution and Dispersal
in the Middle Pleistocene. From Quaternary International.
75: 77-84
Smith,
Fred H., Boyd, Donna C. and Malez Mirko. (1985). Additional
Upper Pleistocene Human Remains from Vindija Cave, Croatia, Yugoslavia.
From American Journal of Physical Anthropology. 68: 375-383.
Smith,
Fred H., Falsetti, Anthony B. and Donnelly, Steven M. (1989).
Modern Human Origins. From Yearbook of Physical Anthropology.
32:35-68.
Tattersall,
Ian. (1999). The Last Neanderthal. A Peter N. Nevraumont
Book, Westview Press, A member of the Perseus Books Group: New
York.
