Micropaleontology: the branch of palaeontology that studies microfossils, or fossils that require the use of a microscope to see the organism, its morphology and its characteristics details. It is the largest discipline in paleontology, just as microfossils are by far the most abundant of all fossils. Although nearly invisible, micro-organisms at the base of the food chain make up nearly 90 per cent of the biomass in oceans and lakes. Changes in the abundance and types of microfossils from year to year, over millions of years of undisturbed accumulation, makes an exquisitely detailed record of climate change, plate tectonics, and biological evolution.