Observation 5: (11/10/2011)

For my 5th observation, I observed a few more new species of organisms. Along with the organisms previously mentioned in my blog, I noted tons of euchlanis rotifers, three nematodes, and a mite. One distinguishing characteristic of the euchlanis rotifers was their motion. The euchlanis rotifers seemed to spiral as they propelled themselves forward. Euchlanis rotifers are known for having two feet for swimming and typically eat bacteria, small protozoans, and other debris (Davidson 2003).

As I continued to observe, I managed to find three nematodes. Each one was partially concealed by either soil or other organic matter. However, it was their quick, writhing movements that caught my eye. Each nematode would slither in and out of the matter, occasionally coming to a standstill. I was stunned to discover that nematodes are " the most numerous multicellular animals on earth". These organisms are known to feed off of fungi, other nematodes, and bacteria. (University of Nebraska-Lincoln,) This may explain why they were all positioned near organic matter, especially decaying organic matter, for this would be the most likely place for bacteria to be located.
Finally, one of my most interesting discoveries was that of a single mite. The mite was to be found in the bottom of my microaquarium in the sediment, the typical living environment of an aquatic mite (Micrographia,). The mite crawled forward very slowly before finally burrowing down into the soil. Something I noticed was that the mite seemed to have a few organisms living on its back such as rotifers, etc.

References

Davidson, M. 2003. Differential Interference Contrast Image Gallery: Euchlanis Rotifer. [Online]. Available from: http://micro.magnet.fsu.edu/primer/techniques/dic/dicgallery/euchlanissmall.html
Accessed 2011 Nov. 14.

What are Nematodes? [Online]. Available from: http://nematode.unl.edu/Wormgen.htm Accessed 2011 Nov. 14.

Hydracarina. Water Mites. [Online]. Available from: http://www.micrographia.com/specbiol/chelicer/mitaqua/mita0100.htm Accessed 2011 Nov. 14.

Observation 4: (11/3/2011)

Today, I noted that there was a tremendous increase in the amount of living organisms in my microaquarium. The numbers of each organism must have at least quadrupled. Upon initially viewing my microaquarium without a microscope, it appeared as though algae of some sort had begun to grow on plants A and B. Like before, my microaquarium contained euplotes, vorticella, and diatoms. However, I found two additional variations of diatoms and a new ciliate within the aquatic environment.
The ciliate, Blepharisma, is known to consume the bacteria that result from dead vegetation (Hanna 2004). Although there were only two that I saw, their presence indicated the decay that was occurring within my microaquarium from dead organisms as well as Plant A and Plant B. The two additional shapes of diatoms that I noticed were square shaped and round with an outer rim that took on the appearance of a star bursting (Sarconid Actinosphaerium). There were well over 50 different diatoms and contrary to last time, I noted movement, namely in the pennate diatoms. The diatoms moved very slowly, appearing to float. 
In regards to the distribution of organisms, I noted that there was a variety of organisms near the soil layer of my microaquarium. Also, where the plants appeared to be brown and in decay, concentration of organisms was greater. This is probably due to the fact that several of these organisms feed on detritus.

References

Hanna, Jannette. Nov. 2004. Blepharisma. http://www.microscopyuk.org.uk/mag/artnov04macro/jhblepharisma.html  Accessed 2011 Nov. 7





Observation 3: (10/28/2011)

My aquatic environment has become more diverse. Today, I found several more vorticella. There were at least 5 this time.

Meanwhile, there were 4 new organisms that I discovered within my microaquarium during this observation: a diatom, a philodina, an amoeba, and an epalxis. 

                                            The diatom is a unicellular organism with a yellow-brown chloroplast                                          and a silica wall. The one found in my microaquarium would be classified                                        as pennate (or pen-shaped) which is the common diatom form in freshwater                                      environments. (Egmond 2006) As I observed my diatom, I didn't notice 

                                     any form of movement. I thought I'd found a dead organism. However, Dr. 

                                     McFarland assured me that it was indeed alive.

     As I was perusing the area around Plant B in my aquatic environment, 

a philodina caught my eye. Partially hidden by one of Plant B's leaves, I 

noticed the worm-like philodina as it would lunge its head out before 

retreating and returning to its original stationary position for a few more

moments. I spotted 2 more of these during the rest of my observation.

A rotifer, philodina eat detritus and small plankton organisms by generating

water currents with ciliary action. The creation of such currents also ensures

that the philodina receive an adequate oxygen supply (Pennak 1953).

 

   In my microaquarium, there was also a single amoeba, a eukaryotic microorganism

                           that moves with the help of pseudopods ("false feet"). Amoeba feed through                                          phagocytosis, a process in which the amoeba engulfs the food particle so as to 

                           consume it (van Egmond Astorienella 2006). It was very interesting to view the                                      slight movement within the amoeba.

     Finally, I observed an epalxis. An epalxis is a ciliate that has the ability to

move extremely fast. Mine would dart everywhere and getting a picture of it

was extremely difficult. However, I was able to get a photograph. My photo

surprisingly captured the hook on the epalxis that distinguishes it from other 

ciliates. This hook can be seen on the left side.

References

van Egmond Asterionella, W. 6 Jan 2006. DIATOMS. <http://www.microscopyuk.org.uk                        /mag/wimsmall/diadr.html>. Accessed 2011 November 1.

Pennak. Freshwater Invertebrates of the United States. New York:Ronald Press Company; 1953.

Food Pellet Time! (10/21/2011)

On Friday October 21, 2011, Dr. McFarland inserted one Beta Food Pellet into my microaquarium.

Pellet: "Atison's Betta Food" 

Made by: Ocean Nutrition, Aqua Pet Americas, 3528 West 500 South, Salt Lake City, UT 84104. 

Ingredients: Fish meal, wheat flower, soy meal, krill meal, minerals, vitamins and preservatives. Analysis: Crude Protein 36%; Crude fat 4.5%; Crude Fiber 3.5%; Moisture 8% and Ash 15%.