Rotifers are microscopic aquatic animals that live in freshwater environments
and are usually found in lakes, rivers, or streams, but can also be found in diverse
areas such as rain gutters, puddles, soil or leaf litter, in sewage tanks, and on
freshwater crustaceans and aquatic insect larvae.
There are approximately 2,000 different species of rotifers.
The name "rotifer" comes from the Latin word meaning "wheel-bearer,"
referring to the crown of cilia around the mouth of the rotifer.
Cilia are hairlike projections that aid in movement and trapping food.
Most rotifers are omnivorous with a diet consisting mostly of dead or decomposing organic materials,
unicellular algae, and other phytoplankton, but some species are cannibalistic.
Rotifers are often preyed upon by shrimp or crabs.
Rotifers may reproduce asexually or sexually.
In sexual reproduction, rotifers produce two kinds of eggs, female eggs, and male eggs, which cannot feed themselves.
The male and female individuals copulate, resulting in a fertilized egg that develops
inside the rotifer, forming a zygote, which then grows into an adult rotifer.
There is a very limited number of rotifer fossils due to their tiny size and soft bodies.
Rotifers are easily observed with the correct procedures and equipment.
A pipette should be used to extract rotifers from a sample, and then quickly transferred to
a slide to prevent the rotifers from sticking to the inside of the pipette.
Cover-slips shouldn't be used on the slide because rotifers are easily disturbed and may contract into a ball.