Sessile vs. Motile Plankton

Phytoplankton, the tiny but mighty organisms inhabiting the vast oceans, come in two main types: sessile and motile. Sessile phytoplankton, much like plants rooted in soil, are stationary, attaching themselves to surfaces such as rocks or other underwater structures. They harness sunlight for energy through photosynthesis, playing a crucial role in marine ecosystems by providing food and oxygen. These organisms, including diatoms and some types of cyanobacteria, form the base of the marine food web, supporting a diverse array of ocean life.

On the other hand, motile phytoplankton are the wanderers of the sea, capable of independent movement through the water column. Unlike their stationary counterparts, motile phytoplankton have evolved mechanisms to propel themselves, either through flagella, tiny whip-like structures, or other means of locomotion. This mobility allows them to better navigate their environment, seeking out optimal conditions for growth and reproduction. Examples of motile phytoplankton include dinoflagellates and certain types of green algae. Their ability to move freely not only aids in their survival but also influences nutrient cycling and ecosystem dynamics in the ocean. In essence, while sessile phytoplankton anchor themselves in place, motile phytoplankton roam the ocean, both contributing to the intricate balance of life beneath the waves.