RAJEEV PATNAIK
Panjab University, Chandigarh
Rajeev Patnaik has adopted a multidisciplinary approach (stable isotopes, dental microwear, microstructure, cladistics, etc.) to address issues concerning Neogene-Quaternary climatic conditions, mammalian ecology, diet, biogeography, chronology and evolution. He and his colleagues carried out cladistic analyses of the Narmada cranium, the only hominin found from India till date, showing a closer relationship to the European Steinheim specimen. He also discovered new hominoids/primates, ostrich-like eggshells, new pelican and darter fossils from the Siwaliks; Late Cretaceous rice from central India; and Miocene mammals from the Baripada Beds of Odisha. In 2016, he was awarded the prestigious National Geoscience Award by the Honourable President of India. Rajeev Patnaik was elected Fellow in 2019.
SESSION 1B: Inaugural Lectures by Fellows/Associates
E D Jemmis
Reconstructing diet and environment of ancient mammals of India using stable isotopes and microwear
Mammalian dental enamel being the hardest biological tissue made up of bioapatite stays unaltered for millions of years. Tooth enamel grows periodically and has the potential of preserving the history of development of the individual and species. The rhythmic growth increments called as the ‘Retzius lines’ outcrop on the tooth enamel surface as perikymata and preserve a continuous record of temporal isotopic changes along the growth axis of a tooth. The carbon isotope composition (δ13C) of tooth enamel in modern herbivores distinguishes between diets dominated by C3 plants (dicots including trees, shrubs, herbs, forbs) and cool season (high latitude or altitude) grasses or sedges, and those dominated by C4 plants (mostly monocots, such as warm-season grasses and sedges). δ18O of enamel, in turn, provides information about the water intake, temperature and rainfall. Study of extinct early primates from India reveals that they were primarily browsers, whereas later forms were grazers. Rats and mice also show similar trends, whereas hypsodonty and isotopes in elephants show shifts in their diets several times in the geological history