Principal speaker
Dr Dafne Koutamanis
Food webs play important roles in Pleistocene vertebrate evolution. Yet, food web reconstructions of Australasian Pleistocene fauna have been hindered by the lack of suitable trophic level proxies when collagen is not well-preserved. Non-traditional stable isotopes, in particular calcium (Ca) isotopes, have the potential to fill this gap, as they can be measured from dental enamel and can indicate an animal's trophic position. In this seminar, I will introduce non-traditional isotopes and their applications to archaeology and palaeontology. I will focus on my PhD project, which explored food webs of Pleistocene Australian megafauna and island fauna from Flores (Indonesia) through Ca isotopes, combined with radiogenic strontium (Sr) isotopes.
First, I will discuss Ca and Sr isotope data from modern Tasmanian bare-nosed wombats and from Pleistocene marsupial mega herbivores from Wellington Caves and Bingara. With the modern data as a reference, the Pleistocene data revealed Ca isotope signatures distinct herbivore diets, indicating future potential research avenues for Ca isotopes in Australian megafauna. Next, I will present a preliminary food web reconstruction of Early- to Middle Pleistocene fauna from the So'a Basin, Flores. In addition to a small-bodied hominin, the So'a Basin was home to multiple reptile predators (Komodo dragons and crocodiles) and mammalian herbivores (giant rats, pygmy-, and medium-sized elephants). So far, the data show how such food web reconstructions can shed light on processes of island evolution in Wallacea.