Radiolarian species are non-motile; they drift along water currents while those currents compartmentalize the ocean into finer ecological domains. Ocean currents carry radiolaria from one water mass to another, so that species tend to have variable reproductive success.

How do radiolarians float?

Description. Radiolarians have many needle-like pseudopods supported by bundles of microtubules, which aid in the radiolarian's buoyancy. The cell nucleus and most other organelles are in the endoplasm, while the ectoplasm is filled with frothy vacuoles and lipid droplets, keeping them buoyant.

How do radiolarians use Pseudopodia?

Radiolarians. ... Radiolarians display needle-like pseudopods that are supported by microtubules which radiate outward from the cell bodies of these protists and function to catch food particles. The shells of dead radiolarians sink to the ocean floor, where they may accumulate in 100 meter-thick depths.