In this study we show the potential of using FB-δ15N to detect photosymbiosis in modern and fossil foraminifera. Due to distinct isotopic signatures related to ammonium recycling, FB-d15N can distinguish between foraminifera with dinoflagellate-symbionts, non-dinoflagellate symbionts and non-symbiotic foraminifera. However, we also point out that in regions with strong oceanographic gradients the application of FB-d15N could be complicated.
So far, there are studies on fossil-bound δ15N in corals, diatoms, otholiths, and teeth (shark, mammal, dinosaur, hominin). In future studies I aim to apply this method to further organisms and geological archives. Together with collaborator Jeffrey Thompson we currently work on modern and Carboniferous sea urchins/echinoids. Other collaborations involve Adriane Lam and Mesozoic ecosystems, and Hana Jurikova and brachiopods.