Observation 1: 10/20/11

Observation 1
Overall, there was quite a bit more life in the MicroAquarium this week as compared to last week. There was about two centimeters of water loss, which was replaced at the end of the observation. The life I saw was quite diverse throughout the three layers of the aquarium.

Top Layer:
The three cyclops were still quite active, and I was even able to observe a cyclops nymph. Both nymph and adult displayed frantic motion, and roamed the entire width of the aquarium in the top layer.
I also observed numerous transparent, single-celled organisms identified as paramecia using the identification books in the lab.
One puzzling feature I observed was the presence of small, vibrating specks. I first believed them to be dirt or dust molecules, but the vibrations puzzled me. I wonder if they are some very small one-celled organisms.

Middle Layer:
In the middle layer, I saw many small, fast moving, transparent organisms only a tenth of the size of the paramecia. I have been so far unable to identify them.
In both the middle and bottom layers were many, many long, green organisms moving slowly. Using a poster in the lab, I identified them as a type of green algae called desmids.

Bottom Layer
Aside from the desmids, I saw some other organisms in the bottom layer. There were two moving rotifers, identified with the identification packet on the lab benches. I also saw a stationary member of the navicula genus, a type of diatom (http://westerndiatoms.colorado.edu/taxa).
I also saw a stationary stentor coeruleus, a type of protozoan, attached to the dirt (http://www.microscope-microscope.org/applications/pond-critters/protozoans/ciliphora/stentor.htm).

Out of all the life observed, however, the most memorable was an organism that I nearly missed. As I scanned the dirt on the bottom layer, I saw some of it moving. With a little focusing of the microscope and a little patience, I began to see glimpses of something worm-like in the dirt. My first view of it head-on came when it extended itself from the dirt to grab onto some plant matter, eat it, then retreat back into the dirt. It was indeed worm-like, and transparent with red dots along it's circular head and elongated body. With the help of Dr McFarland, this odd looking organism was identified as aeolosoma leidyi. Pictures coming soon!