Week 3

This week, week three, my Rotifers were acting abnormal. They were all gathered into one spot , with the exception of the food this was the only place they were concentrated. The location of the concentration was not near the edges, the debris, or the moss , it was just out there in the middle. At first when I began observing this concentration I thought that they may be eggs of the rotifers. As I continued to watch them closely I began to see movement and at different times the round Rotifer looking objects I saw began to stretch out at different times, and then roll back up. I am not sure why they were doing this. At times I saw small Rotifers, looking like they were instigating them. They would come and bump into them as if on purpose, it was really quite interesting. I plan to attempt to find a reason for this action of the Rotifers in my MicroAquarium.

Many rotifers were also concentrated around the edges and around the food. In the corner of the aquarium, they were so dense you could see a orangish color with your naked eye. Around the moss there were many of the little Rotifers. The larger Rotifers seemed to be just sitting around. They had their feet hooked to the glass and they were stretched out all the way and the cilia was going around rather quickly, however the smaller ones were just swimming around and not controlling this action.

The moss seems to be changing some, but not much. It has some small clear strands growing out of the moss, I am not sure why this is occurring or why they are clear. The Debris looks as if it has something growing out of it, I will keep a eye on it and try to determine more in further weeks.

This week in my research, I have discovered many new things about the life of the Rotifers. The Rotifers are multicelular, however they are composed of a relatively small number of cells. Rotifers are also known as “wheel animalcules”. They were first observed by Anton van Leeuvenhoek in 1675. This occurred during his observations of the microscopic inhabitations of water. The Rotifers are found in nearly every body of fresh water. This fresh water includes, but is not limited to, in tiny temporary puddles, in rivers and swamps, and in the largest lakes. They are less encountered in the sea and in marine situations. They appear (as of known in 1955) to be confined to costal regions reaching their abundance in brackish waters. A few species are parasitic, however most species of Rotifers are free-living. The Rotifers, Philodinidae, can be dried up often and even survive through long droughts. Through these long droughts they are able to keep life going at such a low rate that they can survive and resume their normal living after the drought is over. They can even regain their activity after being frozen into the ice for a long period.


~Resources~

Davis, Charles C. The Marine and Fresh-water plankton.. Michigan State University, 1955.

Morgan, Ann Haven Ph.D. Field Book of Ponds and Streams: An Introduction to the Life of Fresh Water. New York & London: G.P. Putnam’s sons The Knicherbarker press, 1930.