Award Holder: Anubhav Preet Kaur
University: Indian Institute of Science Education and Research Mohali
Title of Research: Understanding signatures of hominin occupation the Pinjore Formation (2.6-1.0 Ma) of the Siwalik Hills of northern India using Palaeolithic archaeology, vertebrate Palaeontology and remote sensing
The role of environmental stimuli in hominin evolution, expansion, speciation, adaptation and extinction has been highlighted time and again by scholars. Global climate change from forest-dominated to grassland-dominated environment in the Plio-Pleistocene period has been identified as an important factor for hominin dispersal(s) around the Old World. However, in light of recent researches this priori is being questioned and debated. The fossils of Homo erectus, one of the first known early human species to disperse outside of Africa, has been discovered from Early Pleistocene deposits of East Europe, West Asia, and Southeast Asia, thereby placing Indian Subcontinent in general- and the Siwalik Hills in particular- as an important dispersal route. However, apart from the chronologically and taxonomically ambigous Hathnora cranium, no unequivocal fossil hominin remains have yet been reported from the region. Based on the presence of fauna often associated with Homo erectus, like Theropithecus oswaldi, Hippopotamus, and Megantereon in the Early-Middle Pleistocene deposits of the Siwalik Hills, scholars have predicted the presence of hominin remains in the region, yet none have been found. Currently, lithic artefacts are the only known signatures of hominin occupation in the region, primarily occurring as surface deposits without secure dates. The Pinjore Formation (2.58-0.63Ma), north of Chandigarh, in northern India, represents the most extensive and the only continuous Early-Middle Pleistocene deposit in the region with a rich record of fossilised vertebrate remains and recently, ostrich eggshells. In light of absence of stratified lithic deposits and secure dates, palaeoecological and faunal analogies with other Early-Middle Pleistocene hominin bearing sites, can provide an adequate explanation for presence/ absence of hominins in the region. My research focuses on investigating all possible palaeoanthropological evidences for hominin presence in this region.
The field surveys were focused on the Pinjore deposits of the Siwalik Hills region, north of Chandigarh in northern India. This is the first systematic palaeoanthropological research undertaken in the study area. Field surveys were spread over a period of nine months, two seasons and involved participation from four field assistants, four volunteers and numerous locals who assisted in hospitality, field navigation and excavations. This project received an overwhelming participation from female archaeology students. For most part the field surveys were conducted by an all women team. In contrast to many other smaller towns in India, villagers from the study area were very receptive to an all women team and extended all assistance that we could’ve have required to successfully complete the field surveys. Overall, the Siwalik Hills are undulating with a rugged topography with a high density of thorny bushes throughout the year, making it hard to navigate the landscape. However, with appropriate gear and much help from the locals, field surveys were conducted smoothly.
Apart from its research goals, this project also focused on public outreach and served as an opportunity for prospecting students to engage and learn field methods in archaeology. Such field work opportunities in India are rare and mostly inaccessible due to monetary limitations. Through funding this field work, RAI made it possible for archaeology students to participate and learn. Additionally, all locals involved with the field surveys were also educated about the evidences we were working with and their importance. During excavations, local children visited us regularly and their curiosity only made it easier to educate them. For the most part, the locals were very receptive towards the idea of human evolution and history of life on earth.
As the landscape is rugged, targeted surveys instead of transect were preferred. These were for the most part guided by a site predictive model. Even though lithic scatters have been identified in the study area, they have never been systematically mapped. Hence, the predictive model was generated using data for systematically mapped palaeontological sites from previous expeditions. This model was further supplemented by satellite imagery for field surveys. As a result, eight new localities were identified, namely, Choti Badi Nangal, Jainti Devi, Choti Badi Parch, Tarapur, Bardar, Khol Mola, Gochar and Kakut. These yielded evidence of high to low density fossil scatters and medium to low-density lithic occurrences. Even though lithics and fossil scatters are spatially associated, no direct geological or contextual association between the two could be established. Where the lithic occurrences were concentrated around deflated gravel deposits, fossils were for the most part associated with buff mudstones. At two localities, Kakut and Tarapur, two artefacts were discovered from the surface of buff mudstones along with the fossils. However, nothing in-situ was observed on either the surface or in the trenches. Based on these observations, following predictions are being tested through this project. Prediction 1: Hominins occupied the uplifted Pinjore surfaces during the Later Pleistocene. Prediction 2: There is a lack of in-situ evidence due to rapid erosion on the landscape. Prediction 3: The landscape was not ecologically conducive for the hominins to disperse through. Prediction 4: Limited spatial impact of hominins dispersing through this region.
The first stage of fieldwork focused on targeted field surveys, identifying lithic and fossil scatters, in addition to their context; The second stage was more focused on understanding the contextual association between lithics-fossils, lithics-landscape and fossils-landscape. Two trenches were excavated at Tarapur and Kakut. Unfortunately, no in-situ lithics or fossils were recovered. However, the trenches helped to better outline the stratigraphy at the site. Kakut was a unique case in point. The site stratigraphy is composed of two fossiliferous buff mudstone horizons, separated by a gravel bed (Unit II) and capped by thick, loosely consolidated post-Siwalik gravel. Low density lithic scatters were observed to be associated with unit II gravels only. All artefacts were either observed to be on the surface of the gravel or eroding out of it, with a few having the residual calcrete on them. Lack of fossils in the gravel horizon can be attributed to preservation issues due to high energy deposition. Unfortunately, due to delayed permits no artefacts could be collected or analyzed beyond field documentation. However, they were all documented and photographed in detail on field. Typologically the assemblage can be categorized as simple core and flake and seems to be lacking any advanced morpho-types like handaxes, cleavers, prepared cores, blades etc. Except one thinning flake there is no evidence of any bifacial technology at the site. All fossil specimens were collected and analysed in the lab.
After two seasons of intensive field surveys and excavations, all collected specimens were transported to the lab; where they were cleaned, prepared, catalogued and analysed for taphonomy and palaeoecology. Taphonomy primarily focused on identifying evidence for hominin meat-extracting activities and reconstructing the life history of represented mammals from the time of their death, deposition, burial to exposure. All taphonomic evidences were also compared with specimens from the National Taphonomic Research Collection (NTRC) curated at the National Museum of Natural History (Washington DC) and screened through expert opinion at the museum. Unfortunately, the fossils preserve no evidence for hominin meat extracting activity, mostly due to poor bone surface preservation. Dental ecomorphology and biogeochemical analysis were used for palaeoecological reconstruction. These results were then compared with ecological data from other early Pleistocene hominin bearing sites around the old world. The palaeo-biome of the Pinjore Formation can be described as a wooded grassland with tropical to subtropical climate and high monsoonal variability; similar to the early Pleistocene hominin bearing sites from Africa thereby, indicating presence of a suitable landscape without ecological/ terrestrial barrier for hominins to disperse through. However, despite ecological conducivity, there is a lack of definitive evidence for hominin presence during the Pinjore geochronological timeframe. This lack of evidence can be attributed to various reasons like lack of suitable raw materials, dearth of in-situ evidence, lack of contextually targeted systematic surveys until recently or limited temporal and spatial impact of hominin presence that left no visible evidence during the Pinjore depositional phase. However, these are just hypothesis that need to be tested through future research.