My answer will be because these characteristics intervene in the capture and assimilation of the food, having 4 general food behaviors: (1) detritivores, consume a lot of material from the bottom of the water source, (2) herbivores, who consume mostly plant components (filamentous algae and higher plants); (3) periphyton consumers, who are characterized by feeding on microalgae and microinvertebrates and (4) omnivores, in which they indistinctly feed on plant material as an animal of different origin.
They have longer periods of revolution.
It originates in the inner core of the Earth.