Award Holder: Juliën Kavish Lubeek
University: Macquarie University
Title of Research: Implications for diet and extinction of Gigantopithecus blacki from Pleistocene China based on Dental Microwear Texture Analysis (DMTA)
This project is part of the awardee’s Ph.D. research that pioneers ‘microscopes as time machines’, applied to the cause(s) of extinction of the largest ever hominid: Gigantopithecus blacki (G. blacki). The fossil record of this distant human relative is extremely limited and restricted to karstic caves across southern China. G. blacki roamed the oriental (sub)tropical forests during the Pleistocene (~2.6 million to 11.75 thousand years ago) but mysteriously went extinct during the Middle Pleistocene, while other great apes in the region (such as orang-utans) survived significantly longer. The cause of G. blacki’s extinction is unknown. The awardee’s thesis is part of the overarching ‘Giganto Project’ (https://www.wheregiantsroamed.com/) that attempts to unravel why, how, where and when the giant ape went extinct. As such, the awardee’s thesis aims to reconstruct the environmental and behavioural drivers (the how and where) behind the extinction.
The COVID-19 pandemic caused significant difficulties and prevented the awardee from undertaking field work in China over 2020-2021. Luckily, he already took moulds of original fossils on location in 2019. As such, the Ruggles Gates Scholarship for Bioanthropology was used for lab work only, and has been of great support in enabling the first ever dental microwear texture analysis (DMTA) on fossil G. blacki molars. DMTA can unravel G. blacki’s diet, associated lifestyle and indirectly offers insights in the cause(s) of its extinction.
Originally a ‘multiscalar’ wear study was planned for one paper, incorporating both dental microwear and macrowear. The planned DMTA for that particular paper was supposed to be carried out at Leipzig University, Germany. This was not possible due to travel restrictions and border closures. A subsequent solution was the construction of a ‘self-improvised’ DMTA preparation lab in existing lab spaces at the awardee’s home institute. This enabled the awardee to make dental casts in Australia, with consumables funded by the RAI, after which they could be sent to Germany for scanning. Unfortunately, this part of the analysis was delayed due to extremely impacted shipping times of required high-quality resin, alternative ordering of lower quality resin, and closure of the DMTA Lab. The casts eventually arrived in Leipzig but, until present, still need to be scanned. In addition, the natural history museums of Sydney and Melbourne, where comparative modern orang-utan material was planned to be sampled, were closed in 2020-2021. Therefore, only three orang-utan samples, from the South Australian Museum, were included in the DMTA component of another paper, that was carried out at Flinders University (Adelaide). Some fossil orang-utan and G. blacki teeth at a collaborator’s lab at Southern Cross University (Lismore), offered opportunity for increasing the DMTA sample size. Those teeth, however, were used for other (destructive) techniques first, meaning only those without a cut through facet 9 could be used. After a delay of ~1.5 years, the awardee was finally exempted from travel restrictions and could travel to Adelaide and Lismore to work in different labs with different microscopes and scanning equipment.
Outcomes of this research are relevant for the wider palaeo/bioanthropological community, for three reasons: (1) to gain a better understanding of the regional palaeoclimatic and palaeoenvironmental drivers, and associated primates’ behavioural responses, to the changing conditions during the Pleistocene in (mainland) Southeast Asia; (2) to deepen our knowledge of hominid behavioural-niche relationships (in particular between contemporary G. blacki and orang-utan) in this key region of hominid evolution and migration; and (3) to use these insights for conservation of currently endangered primates, in one of the world’s most rapidly decreasing biodiversity hotspots. Without the Ruggles Gates Fund the awardee would have been unable to purchase consumables for preparation, travel to collaborating labs and collect invaluable data enabling promising results on the diet, lifestyle and extinction of that enigmatic giant hominid.