Foraminifera range from the deepest ocean basins to intertidal zones, from the poles to the tropics, and extend back in geologic time from the present as far as the Cambrian. A single cubic meter of water can contain upwards of tens of thousands of individual foraminifera. Benthic foraminifera living on the substrate can be found in concentrations exceeding one million per cubic meter.

Their obvious abundance and global distribution make these organisms ideal for paleo-environmental analysis and interpretation. Oxygen isotopes preserved within foram tests provide excellent paleotemperature indicators. Specific fossilized assemblages can provide accurate paleodepth interpretation. Distribution studies can demonstrate cryptic movement of water masses within large bodies of water.

The key to unlocking all of these secrets is a simple system of classification in which foraminifera can be readily distinguished or correlated. The simplest method of classification is based on a descriptive morphological analysis. Like most protozoans, foraminifera are genetically specialized in such a way as to maximize their potential under specific environmental conditions. Invariably their simplicity requires that this specialization will be reflected in their overall morphology.