Planktonic foraminifera (colloquially “forams”) are notoriously difficult to culture in the lab. They are incredibly sensitive to disturbance, and require careful and prompt feeding after collection from the water column to ensure their survival. As a consequence, there are only a handful of labs in the world which manage to successfully culture them, and one of them is at the Inter-University Institute of Marine Sciences in Eilat, Israel, where grad student @sophiejgill visited recently, and where this microscope photo was taken.
Foraminifera are probably most famous in Earth Sciences due to their use in palaeoceanography, because the calcite they make their external shells (tests) from records the conditions in the seawater at that time. In sediment cores, once planktonic forams are fossilised, their spectacular calcite spines are not preserved. However, when they are alive, these can be seen clearly using a microscope (but can also be seen with the naked eye!) when the forams are healthy. The species shown in the image above is Globigerinella siphonifera, and there are two individuals here. The life habit of planktonic forams is poorly understood, but their reproduction may be linked to the lunar cycle (!), and their life span is approximately 7 days. As one of the major calcifiers in the surface ocean, more research into how planktonic forams will be affected by climate change, acidifying oceans and geoengineering schemes aiming to enhance ocean alkalinity are important to investigate.
#oxoceanbug #forams #foraminifera #oxforduniversity #earthsciences #biogeochemistry