Pygmy sized human ancestor in Central Narmada Valley a missing link in evolution chain, reveals new study

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During a recent exploration in the Central Narmada Valley, researchers have unearthed skeletal parts of hitherto unknown archaic humans that have inhabited Central Narmada valley in India during late Mid Pleistocene.

Hominin femur fossil  found from Central Narmada Valley
Image Courtesy: Current Science

According to a research communication published in the Current Science Journal, a partial humeral piece (bone which extends from shoulder to elbow), a fragment of the left femur (bone that extends from pelvis to the knee) and other stone artifacts collected from Netankheri, located 3 km away from Hathnora on the banks of Narmada River, shows that Central Narmada Valley had two different archaic human races.

While one was large robust hominins who used to hunt down large mammals with heavy duty weapons, the later developed pygmy sized one which was hitherto unknown to science, used to hunt smaller animals with lightly refined tools. The pygmy sized race could be the real ancestors of all short-bodied populations in South Asia, says the study.

Anatomical differences

Though the humeral piece was 84 mm in length, scientific estimations reveal that the maximum possible length could be 240mm. In that case, it is shorter than that of the known archaic mainland Eastern Indian races. According to the researchers, the humeral piece has more similarities with that of Chaurite Nicobarese populations.

Hominin humerus from Netankheri
Image Courtesy: Current Science 

Though it is not easy to confirm if the fossil belongs to modern humans or archaic hominins, the mineralization and the artifacts recovered along with the fossil suggest the period could be Upper Palaeolithic.

Similarly, the femoral piece is different from that of modern humans. The newly discovered femur, according to researchers, has scarcely developed medial and lateral lips while they are prominently developed into ridges in modern humans. A comparative analysis, according to the research communication, makes it more similar to femur of the Neanderthal man or late archaic hominins.

Thus the newly unearthed humeral fossil may belong to a connecting link between the short statured archaic humans to the early modern homo sapience during the late Pleistocene, says the study.

Culturally different race

Excavations at Hathnora earlier have revealed the existence of archaic hominin populations on the Narmada banks dating back to mid- Pleistocene age. However, the present findings, when compared with that from Hathnora, reveal that the races were culturally and physically distinct.

Substantiating the findings, the study points out that the faunal fossils and the types of artifacts recovered from the two sites are different, which in turn suggest that the races were culturally different.

a. Bone and stone implements associated with human humerus at Netankheri and similar sites. b, Small mode 3 lithic implements excavated at Hathnora clavicle site; such tools were also recovered from Netankheri humerus site.
Image Courtesy: Current Science 

During the excavation at Hathnora, researchers have unearthed a complete mandible or lower jaw of Equus namadicus, a pre-historic era horse like mammal of Narmada valley. Interestingly, a portion of its lower jaw had a pre-historic tool struck in it, pointing out that the animal was contemporary with the man who made these tools.

 Similarly, current excavations at Hathnora partial skull level have yielded a large cache of heavy duty artifacts, many of them associated with large mammalian fossils, suggesting that the Hathnora populations known by the skull were large robust humans and they used to hunt down large mammals also.

However, excavations at Netankheri at the same level yielded very few large mammalian fossils and very few heavy duty artifacts. Researchers were able to unearth some lower jaw remnants of Stegodon insignis ganesa, a pre-historic elephant known for its longer tusks, and very few heavy duty artifacts from Netankheri. While the artifacts at Hathnora contained Picks, chopping tools, cleavers and hand axes, not many similar tools were present at Netankheri. However, the picks recovered from Netankheri at femur level were culturally similar to those of Hathnora skull level and connect the two robust fossil findings.

Map of a portion of the Central Narmada valley
Image Courtesy: Current Science 

All these signs, point to the fact that the races were physically and culturally different, to the point that the short-statured race used to hunt only smaller mammals and used more refined tools, than the robust humans in Hatnora. “The fossil and archaeological evidence from Hathnora represent two types of culturally and physically distinct, anatomically archaic hominin populations in the Central Narmada Valley.”, says the paper.

Connecting link to modern human populations on Narmada Valley

These findings throw more light into the evolution of human race in South Asia region. According to the research communication, the humeral piece of fossil belonged to a type of human race which could be a connecting link between short statured archaic human races in Narmada Valley during later Middle Pleistocene to the modern Homo sapiens in the evolutionary chain.

Possibly, the present short bodied South Asian populations could be descendants of this ancestral root. According to the study, the present Munda settlements in Narmada Valley who have phylogenetic similarities with Andaman Pygmies, can be the present continuation of this short statured human race who inhabited the place during late Pleistocene.

According to Dr. A R Sankhyan, the lead author and a retired palaeoanthropologist with Anthropological Survey of India,   the short and stocky people can even be the ancestors of African pygmies. In a media statement, Sankhyan said that the race "could be the ancestors of the short-bodied people of south Asia, those found in the Andaman and Nicobar Islands and African pygmies".

Early human populations in Narmada Valley

Excavations and palaeontological explorations in the Central Narmada Valley have given valuable insights into the prehistoric age with faunal fossils and stone-age artifacts since 1830s. However, the first direct door of knowledge to the archaic human populations here was opened when a partial hominin cranium was found in 1980s. Later, two clavicles and a partial 9^th left rib also were recovered from Hathnora.

However, the mismatching nature of the recovered fossils has always suggested the chances of presence of more than one human race in Central Narmada valley.  The present study also points out that the archaic human settlements extend to other places on the banks of Narmada like Netankheri which calls for more studies to unravel the mystery of Central Narmada Valley ancestors. 

Rajasthan had lagoons with evergreen vegetation, 55 million years ago, says paleontologists

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Rajasthan is known for the dry geography including the great Thar Desert.  However, it had lush evergreen vegetation with lagoons about 55 million years ago, says a new study, as palentologists have found the fossil of a coconut like fruit from the Kapurdi village in Barmer district of Rajasthan.

Fossil of a 55 million year old fruit Cocos Sahnii from
Kapurdi village in Barmer district of Rajasthan
(White arrows shows the eyes and black ones show ridges)
 Image courtesy: Anumeha Shukla, Rakesh C Mehrotra and Jaswant S Guleria

According to the study which is published in the latest issue of the Journal of Bioscience, the fruit has close relation with the present day coconut palms. It indicates that the environmental conditions in the area were supportive to the growth of coconut like palms which are usually found in the coastal ecosystems with relatively good rain fall, says the study.

“Its presence indicates warm, humid, possibly coastal conditions during the Early Eocene in Rajasthan, in contrast to the present-day dry and desertic climatic conditions occurring there. This finding, along with earlier described evergreen taxa at the site, indicates that the climate of Rajasthan was much better and luxuriant to support the growth of these evergreen taxa”, says the study.

Moreover, the new finding is also in line with earlier studies which have recovered fossils of evergreen vegetation, crabs, fishes, turtles and other aquatic organisms from here, indicating the existence of lagoon like ecosystems 55 million years ago.

According to the study, the uplift of the Himalayas and the Tibetan plateau could be the reasons which have contributed to a drastic change in the environmental conditions of the region, making it dry and arid.

A close relative of today’s coconut

The fruit fossil has two eyes and longitudinal ridges on the surface, making it similar to coconuts. The fibers of the husk are also longitudinally distributed as in a coconut fruit, says the study. Moreover, the 11.7 cm long and 5.8 cm wide fibrous fruit in ovoid shape resembles Cocos nucifera fruit than that of any other subspecies among the coconut palms.

The fruit was earlier identified as Cocos sahnii, when famous botanist Professor Kailas Nath Kaul found its fossil from the same area in 1951. But the study did not scientifically describe the species, as the fossil was an impression of the hard inner layer of the fruit on a stone. However, the new study has analyzed another fossil which has the mesocarp of the fruit (which is similar to the husk of the coconut fruit) intact, to establish its relation with coconut fruits.

Anumeha Shukla, Rakesh C Mehrotra and Jaswant S Guleria of Birbal Sahni Institute of Palaeobotany, Lucknow has conducted the study.