THE (IN)CONSISTENCY OF LINKS ACROSS TRAITS, SPECIES AND COMMUNITIES IN PLANKTIC FORAMINIFERA DURING PLIO-PLEISTOCENE CLIMAT CHANGE

RATIONALE

Extinction is a very real threat: we are already seeing ongoing declines in biodiversity. The IPCC has predicted rapid environmental changes for the next 30-80 years that will result in a further loss in beneficial systems within the ecosystem, such as the providence of goods and services (food, materials, medicines, etc.) and the regulation of climate conditions suitable for humans. Therefore, it is vital to understand biodiversity and the drivers of extinction to understand the risk of anthropogenic climate change.

PROPOSAL

Both biotic and abiotic factors control diversification and extinction. Climate change, mostly temperature, is widely suggested as the main abiotic control on macroecology and macroevolution. Identifying biotic regulators of biodiversity change in deep time is more complex because we typically cannot directly observe biotic interactions. In taphonomic settings that preserve multiple individuals, we can make progress by reconstructing community dynamics. Therefore, using the spatially, biogeographically, and taxonomically comprehensive fossil record of Plio-Pleistocene planktic foraminifera allows for high-resolution studies of the long-term eco-evolutionary response to environmental change that cannot be measured using molecular phylogenetics.

HYPOTHESIS

A study of planktonic foraminifera from tropical Atlantic ODP Site 925 will therefore be used to investigate common driving mechanisms and early warning signals of extinction over the past 5 million years. There is potential to gain an understanding of how biotic forces shaped past extinctions, which can be used to predict future extinctions under climate-driven extinction threats. It will also develop methods to quantify whether incumbent species are at an advantage compared to new or invading species by already occupying an environmental niche and, therefore, avoiding extinction. Incumbency advantage has been evoked as a biotic mechanism for biodiversity changes but has not previously been measured due to the challenges of quantifying it.

METHODS

Species’ reactions to climate change will be assessed using assemblage data and morphological measurements. Novel statistical analysis will be used to analyse and compare the foraminiferal data to the environmental data. These methods will not only deepen our understanding of the drivers of extinction in planktic foraminifera but will also assist in determining whether incumbency advantages buffer against climate change and the impact of extinctions on ecological dynamics in deep time.

RESULTS

Coming soon to a journal near you!