In culture containers with sediment on the bottom, two of six species of planktic foraminifera reveal characteristic benthic activities, such as reorientation, crawling, and burrowing. Globigerinella siphonifera creates well-organized burrows and excavated sediment on a circular pile. Globorotalia menardii and Globigerinella siphonifera have specific crawling and burrowing orientations, with crawling speeds of up to 1 mm/min and burrowing speeds of 0.5–2 mm/hr. Globigerinoides ruber, Globigerinoides sacculifer, Hastigerina pelagica, and Orbulina universa did not exhibit any benthic activity and died on sediment substrates. The ability to live in a benthic mode may be a strategy in species adapted to the deep chlorophyll maximum, or neritic environments, where they exploit floating organic aggregates (marine snow) as a pseudobenthic habitat and a source of food. Benthic and pseudobenthic behavior may have been widespread in Mesozoic planktic foraminifera and may explain their widespread occurrence in epicontinental seas.

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