It was in 1934: Ramapithecene molars, partial maxillae and mandibles were reported by Lewis [9] and a great exercise was conducted to reconstruct not only its cranium, but a hypothetical model of its entire body structure. Presumably, an occasional bipedal gait was also presumed. Ramapithecus was stocky, but short and slender built.

Now all the Indian Siwalik Mio-Pliocene great apes viz. the Gigantopithecus, Sivapithecus and the Ramapithecus have been basically grouped under one single taxon, the Sivapithecus. The term Sivapithecus was however coined by Pilgrim [13]. Primary basis of this grouping has been the excessive thickness of enamel on the occlusal surface of check teeth and not the dental-gnathic pattern alone. The incisor-form canines have also not been of much support to keep the classical Ramapithecenes in family Hominidae [12]. In context with the evolving hierarchy, Prasad's logic [14] appears befitting that “the occurrence of many of these advanced apes and Ramapithecus, the Siwalik of India formed the radiation centre for the evolution of man”. Prasad further goes on to add that “Siwalik hills and Narmada valley hold key to the future exploration pertaining to the origin and evolution of primates.” And that proved true.

When the Ramapithecus remains have been put as antecedents to the present-day orang-utans, little scope is left to fill in the phylogenetic void prior to the Hathnora Homo erectus individual in human or pre-human lineage.

The geographically nearest H. sapiens that have been studied by Wakankar (personal communication) are from the well-known UNESCO Heritage caves of Bhimbetka, located barely 40 km northwest of the Hathnora Homo erectus site (Fig. 2a). The Vindhyan caves, rock shelters complex, well known for rock paintings, have also yielded bones of 10 000–12 000-year-old Homo sapiens (Fig. 1) with highly evolved features in a dorsally enlarged neuro-cranium, although there are innumerable caves in the low-dipping Vindhyan quartzite strata comprising the Vindhyachal mountain range that runs very close to the Narmada River channel on its northern side. The Bhimbetka complex is however much different from other rock shelters and since there is practically no stratified cave deposit of prominence, the chances of getting human or other cave dwelling animals are very meagre. However, the thick pile of debris, just in front of these rock shelters, appears to be a potential ground for locating remnants of possible inhabitants.

The artefact sites in the sub-continent are numerous, but if we take into account the human skeletal remains, the geographically next location is that of Sarai Nahar Rai and Mahadaha remains of the Pratapgarh district of Uttar Pradesh [15]. These remains were dug up accidentally during construction of irrigation canals. A large number of basal Holocene human remains with modern features have been systematically excavated here by Allahabad University scholars. Still older or contemporary could be a mandible from the later Pleistocene Mogasarayanigondi cave deposits in Kurnool district, of Andhra Pradesh (Fig. 2b) [3] with broad retromolar area and large mental foramen. This individual appears to be an aging adult surviving in a hibernating environment. In an overall granitic terrain in the southern peninsula, very thin veneer of alluvium is observed. Though excellent primary Palaeolithic sites have been reported from this part of the country, yet only one human tibial part is reported from the Attirampakkam area near Chennai [5].

Most famous and culturally very deeply studied Homo sapiens skeletons have been unearthed from the five-millennium BC-old sites of Harappa (Fig. 2c). and Mohenjodaro. These localities are now in Pakistan. Their chronologically contemporary sites have been discovered by the Archaeological Survey of India in Dholavira, Lothal and Kalibangan in western and northwestern India.

The Bronze Age Harappan skeletons show advanced physical evolution. Specifically the skulls sometimes exhibit hyperdolichocephaly, the glabella is massive, the frontal region is low and steeply inclined, the supramastoid crest is in mere traces. Orbits have sharp margins, and a low mid sagittal keeling is also observed. Some of these features are common to both Asian and European modern-day humans. The regional population of Harappa, Mohenjodaro and Lothal exhibit heterogeneous characters.

Fossil evidences of anatomically modern Homo sapiens have been recovered from Batadombalena caves besides Belanbandi Palassa, Belilena Kitulgala area in the Sabaragamuva Province near Kuruvita, in central Sri Lanka [5] (Fig. 2d). Kennedy et al. [7] have given a summing up account of the discoveries of the human skeletal remains of ancient Sri Lankans that have been dated around 30 000 years utilizing radiocarbon and thermo-luminescence dating methods for the prehistoric deposits. Human fossils resembling the Sri Lankan ones are yet to be discovered from the Indian sub-continent.

The Darra-i-Kur Homo sapiens of Afghanistan [6] is of equal antiquity to that of the Sri Lankan skeletal remains. The skeletal remains comprise a broken right temporal bone of both Neanderthal as well as modern Homo sapiens affinity (Teshih Tash Shanidar El Kowm) [2]. This is the only human fossil link between Ubeidiya in the Levant and Narmada.

The Narmada Homo erectus remains (Fig. 3) comprising fairly complete neuro-cranium [10], [11] and [16] have provided evidence of early human existence in peninsular India. For quite long, the Narmada Valley has yielded one of the richest collections of gradually evolving Pleistocene mammals in their stratigraphic disposition. The Narmada Homo erectus possesses some of the typical Homo erectus features based on both metrical and non-metrical features summarised by Andrews [1], viz., the very low disposition of maximum cranial breadth, flat and gently receding frontal, strong and bulging mastoid and supramastoid crests, opisthocranion coinciding with inion, pronounced post-orbital constriction, strong supraorbital torus, flat parietal, low temporal squama, angularity between the axis of the petrous bone and the thick tympanic plate, the later being in coronal plane, the upper squama being shorter than the lower in the occipital bone, strong but abraded occipital torus, thick external and internal tables of skull wall, metopic prominence, a median keel in parietal junction area, flanked by parasagittal depressions, and a clearly brought out bregmatic eminence. Kennedy et al. [8], utilizing multivariate analysis and highlighting negative factors only, however, differ in taxonomic assignment and prefer to designate the Narmada cranium as ‘archaic’ Homo sapiens [4]. Kennedy et al. [7], however, quote that “the Narmada calvaria is the only well-preserved and authenticated discovery of a Middle Pleistocene fossil hominid recovered from the Indian sub-continent and its geographical mid-point situation between the east and relatively richer fossil hominid sites in far Est and Southeast Asia, and in the Eurasian and African land masses afford it a unique place.” The Narmada Homo erectus was excavated along with typical Middle Pleistocene fauna, like Stegodon namadicus and Sus namadicus in the gravel conglomerate layer in which it was found in situ just overlying the Matuyama–Brunhes palaeomagnetic reversal shown by deeply oxidised silt. This reversal is dated at 0.78 Ma [17].

The morphological features of the progressively evolved humans in the sub-continent show a kind of biological continuity disseminating from Narmada in the central India to Sri Lanka towards south and from Sarai Nahar in north and further to Lothal, Mohenjodaro in the western part of sub-continent. The gaps in the records of skeletal remains are substantiated by the relicts of cultural activity and that would hopefully help us to find more skeletal evidences. With the Hathnora Homo erectus specimen in core area, a gradual evolution to modern Homo sapiens could be inferred.