EAR PF: Examining paleoclimatic influences underlying Pleistocene-Holocene mammalian dietary ecology and trophic positioning in mainland Southeast Asia

Dr. Alliya Akhtar has been awarded an NSF EAR Postdoctoral Fellowship to carry out research and education plans at Princeton University and William Paterson University. As global climate, hydrology and human land uses continue to change, the full extent of the impact on biodiversity and ecosystems is a topic of great interest.

Today, mainland southeast Asia is one of the world’s most vulnerable regions to climate change. For example, even slight changes in the intensity and timing of the monsoon rainfall can significantly impact the billions of people who live in this region, by affecting water supplies for human use, agriculture, and faunal assemblages. This research aims to better understand the interplay between these aspects in the present day, and the possible impact on future ecosystems, by looking at the geological record.

The end-Pleistocene (11,700-years ago) to mid-Holocene (5,000-years ago) period of mainland Southeast Asia represents a critical interval in the co-evolution of climate, natural ecosystems, and human societies. This period includes the termination of the last great ice age ∼ 10,000-years ago and a dynamic and variable Asian monsoon. Associated increases in temperature and precipitation likely influenced the biotic resources of the region.

In addition, changes in land use by human populations at this time likely resulted in landscape changes from new agrarian and subsistence-based practices (including forest clearance) that could have further impacted faunal assemblages and affected regional climate and hydrology. The development of a comprehensive, multi-proxy record will aid in understanding the role of paleoenvironment on faunal food-web dynamics and evolution of human behavior.

Dr. Akhtar will also involve students from historically underrepresented minority affiliations (especially undergraduates from William Paterson University, a designated Hispanic-serving institution) in every aspect of the research project through summer research experiences and mentorship through senior thesis and capstone projects.

Dr. Akhtar’s research agenda will follow three themes. First, exploring the utility of novel geochemical proxies (including stable isotopes of calcium, magnesium and zinc) for trophic level dynamics in modern mammalian taxa with known foraging behaviors.

Second, leveraging the results of this multi-proxy survey to help to guide the interpretation of similar studies conducted across a variety of terrestrial faunal materials, including late-Pleistocene and Holocene aged fossil tooth assemblages from southeast Asia. Third, conducting trace-element uptake experiments to study the incorporation of uranium (U) and other rare earth elements (REEs) in hopes to refine models of diffusive uranium incorporation and U-series dating protocols for accurate and precise age determination.

Together, these three nodes constitute an important foundation for testing the impact of changing regional and local hydroclimate on megafaunal trophic level and food web dynamics in southeast Asian from the Late Pleistocene to mid-Holocene, and have profound implications for projecting ecosystem behavior in the future.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.