Rotifer Photos

I have a couple of students working with me this summer on an ethogram of my rotifers. An ethogram is a list of behaviors exhibited by a species, with a description of each one. One of the students, Laura is particularly interested in invertebrate behavior, and the other, Harmony, wants to get experience in scientific illustration. Harmony will make the illustrations of that go with the descriptions of each behavior.

In order to help her with this, I am figuring out how to get good photos of the rotifers through a compound scope. Here are some of the prototypes:

A juvenile female rotifer feeding on bright green algal cells.

This very small female (on the right) dwarfs the normal sized male on the left. Male rotifers are tiny, fast and anatomically simple. He has no digestive system, a very rudimentary foot, and no defensive spines. The very dark area in the middle of the female is her trophi (aka teeth). The male has none. His penis is at the base (caudal end) of his foot, and he is attempting to inject sperm into the female.



This juvenile female has retracted her head and foot into her shell (lorica) in a defensive posture, because I poked her with my pipette.


This is a high magnification shot of a dried out male rotifer. The males never hold still and are very hard to get photographs of in life. I dried this male onto a microscope slide with a lamp. On the left you can see his shaggy 'mane' of cillia, which propel him through the water. The males are very small compared to their cillia, which may help to explain why they are so damn fast.