Biology

temperature

humidity

light

rainfall

water conservation

securing mate

protection and defense

escaping adaptation

disease

drought

competition

natality

Decaying organic matter remains afloat.

Largest and medium size particles settle at the bottom.

Remains of decaying organic matter settles at the bottom.

Largest soil particles remain suspended in water.

Euglena

Hydra

Onion bulb

Paramecium