For example, cranial wall sides slightly convergent upward or vertical (parallel) in rear view, which could transform into the high pentagonal shape displayed by H. sapiens as well as the rounded contour exhibited by H. neanderthalensis. In addition, the location of opisthocranion on the occipital plane of the occipital squama precedes the bulging occipital bones (although different in form) of Neanderthals and modern humans. These features are linked with a cranial capacity that is larger than that of H. erectus but smaller than in modern humans and Neanderthals.
Features exclusive to this and other European Middle Pleistocene populations. These features are not interpreted as a late stage in the transformation sequence of a derived character state but as intermediate character states in a postulated sequence of change (morphocline) that leads to the apomorphies of the Neanderthals. They are thus both primitive and derived. The anatomy of the occipital torus and that of the suprainiac area are a good example. The midface and the supraorbital torus are another.
Primitive features retained in H. sapiens but lost in the Neanderthals, such as the size and shape of the mastoid process.
Primitive features lost in H. sapiens but retained in the Neanderthals, such as the absence of a chin.
Derived features unique to the Neanderthals (autapomorphies), such as the retromolar space of the mandible.
The postcranial skeleton, in particular the pelvis, is primitive and does not show the modifications from the archaic design seen in Neanderthals, such as the thin superior pubic ramus. In principle, autapomorphies have not been found in the Sima de los Huesos, which would exclude them from forming part of a chronospecies in the evolution of the Neanderthals, but this is because the unique features that are found (in this and other European middle Middle Pleistocene fossils) are interpreted as character states that are intermediate in their polarity. The amount of time between the fossils from the Gran Dolina (terminal Early Pleistocene) and the appearance of Neanderthals and modern humans (toward the end of the Middle Pleistocene) is sufficiently long (≥500 kyr) to be able to recognize other similar entities, like that at the Sima de los Huesos, in Europe or Africa.
Although we cannot compare the Sima de los Huesos with any other collection (because they do not exist), we can ask whether it is possible to find a fossil within the Sima de los Huesos sample with characteristics like those seen in the mandible of H. antecessor from the Gran Dolina or the Mauer mandible (Germany) or in the crania from Ceprano (Italy), Petralona (Greece), Swanscombe (England), or Broken Hill (Zambia). The fossil from Ceprano was even designated as a new species (Homo cepra-