The origin of H. The window between 1, and thousand years before present appears of crucial importance, including the generation of a new and more encephalised kind of humanity, referred to by many authors as H.
This species greatly diversified during the Middle Pleistocene up to 2 italian homo formation of new variants i. It is proposed to separate the hypodigm of a single, widespread, and polymorphic human taxon of the Middle Pleistocene into distinct subspecies i. The ancestral one should be H. The origin of anatomically and genetically modern humans H. This paper aims at investigating such a new frontier for paleoanthropology. It will focus on topology, chronology, tempo, and mode of the main evolutionary nodes before the appearance 2 italian homo H.
When considering all the available data, we are confronted with a comprehensive scenario about the deep roots of our species. The special case study provided by a well-known fossil specimen from Italy—that is, the calvarium from Ceprano for a review, see [ 8 ] —may help to see the remote origins of H.
Views about the origin of our own species greatly changed during the last couple 2 italian homo decades, involving our interpretation of the evolution of the genus Homo as a whole. The paradigm of 2 italian homo century, shared among many scholars until recently, was based on the existence of a single human species that evolved gradually and sequentially during the entire Pleistocene: Consistently with this perspective, the current human diversity would have been the result of small and constant changes among populations and within the species as a whole viewed as a single, extremely large population taking place from the original geographical diffusion of the genus Homowhere the roots of the present human diversity would be found.
As a consequence, the taxon H. It is well known that according to the model introduced by Wolpoff and colleagues [ 12 ] the anatomically 2 italian homo populations of Africa, Asia, and Europe have been viewed as emerging in continuity with the preceding archaic humans of the same geographical area.
This observation, however, has been contradicted by a 2 italian homo of works [ 1314 ] and, more in general, the model is regarded as not in agreement with most of the paleogenetic data since the seminal work by Cann et al. To a large extent, this view has now been abandoned, after a debate that lasted for more than two decades [ 16 ].
Some of the issues of this scientific revolution sensu Kuhn [ 17 ] may be summarised with reference to Figure 1 and are briefly discussed below.
Note that, according to this scenario, only H. One of the consequences of the middle-century paradigm on the interpretation of the fossil record was that a single species, H. However, an increasing number of data—including the evidence coming from the Georgian site of Dmanisi [ 1819 ]—suggests a different scenario.
The same corpus of data suggests that this process should have started well before the appearance of either H. Within this 2 italian homo approach, H. Alternatively, these two geographical variants are grouped under the definition H.
At the same time, other species have been named or old nomina have been reconsidered, and they include according to the chronological order of references that are pivotal for the 2 italian homo debate: Moreover, 2 italian homo confers a clearer, more intelligible significance to human varieties that were formerly hidden, being referred either to H.
Looking at Europe, the relatively best known regional example, at least two distinct waves of immigrants seem to be recognizable between the late Early and the early Middle Pleistocene. In terms of fossil record, the former wave is documented at present only in Spain and is referred to H.
As a matter of fact, this species occurs in two sites of the Sierra de Atapuerca, near Burgos: These fossils are generally included within the species H. Alternatively, it is H. In a sense, the Sierra de Atapuerca provides the evidence that could explain this ambivalence, either in the former or in the latter direction. At the same time, however, it should be remarked that the material from Sima de los Huesos is clearly Neanderthal oriented, being characterized by a number of features that, later in the Pleistocene, will become typical of the Neanderthals [ 3839 ].
Looking at the material from Atapuerca SH, therefore, H. There are, anyway, in Europe other fossil specimens—such as the calvarium from Ceprano, Italy see discussion below —that are penecontemporaneous with the material from Atapuerca SH and might 2 italian homo far better than the Spanish sample a possible ancestral morphotype for H. Hence, these sub—Saharan specimens of the late Early Pleistocene signal a morphological discontinuity with the subsequent fossil record 2 italian homo should be considered 2 italian homo late representatives of H.
Thus, the differences occurring between H. More in general, late H. These, in turn, are also respectively distinguishable from H. To sum up, at present, 2 italian homo chronology, topology, and phylogenetic dynamics related to the geographically dispersed and rather synchronous appearance of Middle Pleistocene humans—or H. Ultimately, the provenience of those archaic humans see question mark in Figure 1 that, in turn, were ancestral to the origin of both Neanderthals and modern humans is not evident [ 14041 ].
A possible answer comes from the results recently obtained with the analysis of the complete mitochondrial DNA mtDNA sequence retrieved from the isolated human phalanx of the Denisova cave in the Altai mountains, southern Siberia. The mtDNA evidence surprisingly points to humans that were different from both H.
As visible in Figure 1the origin of these three 2 italian homo corresponds well to the morphological discontinuity occurring in the fossil record before the appearance of H.
Researchers opted to wait for their data to provide a clearer picture of the relationship with Neanderthals and 2 italian homo humans before giving the hypothetical unknown species a formal name. Assuming in fact that H. Further analyses on the Denisova material—including exceptionally preserved nuclear DNA from the phalanx and the discovery of an upper molar—drove the same group of researchers to publish additional data [ 44 ], which appeared when the present paper was 2 italian homo revision.
They confirmed that the Denisova individuals, and the population they belonged to, exhibit molecular mtDNA as well as morphological dental features that appear extremely archaic.
By contrast, the picture that emerges from the analysis of the nuclear genome suggests that this human group has close affinities with the Neanderthals, larger than expected 2 italian homo the mtDNA. Evolutionary tree of H. The main evolutionary trajectories dashed-bold lines and the maintenance of gene flow between populations of distinct lineages GF are in accordance with a combination of paleogenetic data reported by Krause and colleagues [ 42 ] and by Reich and colleagues [ 44 ].
According to this scenario, Ceprano 2 italian homo represent one of 2 italian homo latest representatives of the most archaic variant of H. Localised interspecific hybridization between H. This substantiates previous conclusions based on morphology and palaeogeography, which suggested isolation and divergence between the European and African lineages during the Middle and the early Late Pleistocene after Santa Luca [ 38 ]. As a matter of fact, looking at the hypodigm of H.
At the same time, phenotypic variation has to be noted also at the regional level, such as within the European fossil record of the Middle Pleistocene, now greatly expanded by the recently revised chronology of the calvarium from Ceprano [ 49 ].
Its discovery represents the result of systematic field activities conducted for decades in southern Lazio by the Italian Institute of Human Palaeontology under the supervision of the Soprintendenza Archeologica del Lazioand particularly by I. On March 13thBiddittu found a first cranial fragment during a survey along the trench excavated for a new road while other portions of the same cranium were still included in the nearby section created by the excavators.
Subsequently, all the fragments about fifty were carefully extracted and sieved from the clayey sediments. The reconstruction of the cranium required more than one attempt, the intervention of a composite team, and, overall, about five years [ 626467 ].
For the purpose of a chronological reference, the geologist A. Segre [ 6267 ] suggested a compilation stratigraphic column at a microregional scale, mainly based on previous geopalaeontological knowledge. Consistently, the archaic features of the calvarium were considered in 2 italian homo with Mode 1 technocomplexes coming from sites scattered in the Ceprano basin [ 57 ], although a number of Acheulean assemblages are also well known at Campogrande and surroundings and are now submitted to an accurate reappraisal [ 49 ].
With these premises, a project of surveys and excavations started in under the direction of I. Manzi, with a threefold aim: Segre; 3 improvement of the palaeontological and archaeological records. This result is also consistent with the normal 2 italian homo polarity recorded in the area of discovery down to a depth of about 50 metres [ 68 ].