High proportions of abnormal tests may result from natural stress resulting from either extreme environmental conditions or from rapid changes in ecological parameters.

Based on the studies of Boltovskoy et al., 1991;

    He claimed that morphological test variations in benthic foraminifera are related to several environmental parameters such as:

temperature, salinity, carbonate solubility, depth, nutrition, substrate, dissolved oxygen, illumination, pollution, water motion of trace elements and rapid environmental fluctuation.

These parameters can be analyzed by gathering preserved specimens of buried tests in the substrate.  Afterwards, one can get an idea what factors effected the environment and the forams that inhabited this ecosystem.