Final MicroAquarium Observation

For my last observation, I noticed that a lot of water had evaporated from my MicroAquarium and that both plants present in my aquarium looked very unhealthy due to feeding by the aquatic organisms.  The Amblestegium sp. moss appeared to be the preferred food source among the microorganisms because it looked like it was fed upon the most. With the noticeable depletion of plant material, came the apparent slowing down of life in my MicroAquarium; organisms seemed to move slower, and their relative abundance seemed to have decreased slightly.  I still saw a few Tachysoma sp., Euplotes sp., Actinosphaerium sp., Vorticella sp., and Euchlanis sp.  The midge that first appeared during my previous observation was still alive and active during my final observation as well.  Most of the activity that I noticed during this observation occurred near the soil surface where I saw a lot of diatoms, rotifers, and Euplotes sp.

Around the middle of my MicroAquarium, it looked as though the diatoms I saw during my last observation had taken on a new shape.  I saw a lot of bright green, linear, spiky, glass-like organisms arranged in a clumped fashion (Figure 1).  Through some research Dr. McFarland and I concluded that this living creature was probably an Ankistrodesmus sp. (Smith 2001).  This green algae is usually found in freshwater lakes and ponds and it is usually arranged in parallel bundles, with some bundles which rotate, giving the colony a spiked appearance (Algaebase 2011).  More information on the Ankistrodesmus sp. can be found at http://www.algaebase.org/search/genus/detail/?genus_id=44102&-session=abv4:D860C4D31b20707C6ARno2C5C147.

I thought I had discovered a new species in my MicroAquarium when I saw a beetle-like organism crawing up one of the plants.  It looked as though it had legs.  When I asked Dr. McFarland about the organism, he informed me that it was a Euplotes sp., which I had already identified in my MicroAquarium two weeks ago (Figure 2).  Upon further research, I learned that the Euplotes sp. have large cilia that is tufted together to form cirri, which help it to "walk" along objects (Microbus 2010).  When I first saw these creatures, they were gliding along the water in my microaquarium, rather than "walking" on objects, so when I saw them "crawling" up the plant steams, I thought I was witnessing a different type of organism.  More pictures of these fascinating creatures can be found at http://www.microscope-microscope.org/applications/pond-critters/protozoans/ciliphora/euplotes.htm.

I also saw more Tachysoma sp. in my MicroAquarium, and they seemed to be the most abundant during this observation session.  I was able to take a better picture of this organism as well (Figure 3).

While closely inspecting my aquarium, I saw few organisms that looked like clear blobs of different shapes with little spheres moving inside of them.  I was able to identify them as Amoeba sp. (Figures 4 and 5).  Amoebas are single-celled organisms that can take in food by surrounding and engulfing it (FCPS 2011).  These bits of food and other particles are probably what I saw floating around in the amoeba's cytoplasm.  Interesting facts on amoebas can be found at http://www.fcps.edu/islandcreekes/ecology/amoeba.htm.

Lastly, I saw a beautiful Gomphonema sp. (Figure 6).  It looked like two golden flowers which were connected by their stalks.  It also had a shape similar to the Vorticella sp.  According to Freshwater Algae: Their Microscopic World Explored, the Gomphnema sp. have a stalk, which can be branched to form a tree-like shape and that they spend most of their lives attached to a substrate.

Overall, my last MicroAquarium observation was very productive and enlightening.  I enjoyed doing my observations over the past 5 weeks, and I particularly liked learning about each of the individual microorganisms.  Each creature had its own unique features, which always sparked my interest.  Hopefully, the general public will look upon my blog as an interesting account of the secret life of microorganisms.



Figure 1 (corresponds to Figure 180 on page 265 of Fresh-Water Algae of the United States, second edition)




Figure 2 (corresponds to Figure 260 on page 124 of Free-Living Freshwater Protozoa: A Colour Guide)




Figure 3 (corresponds to Figure 265 on page 125 of Free-Living Freshwater Protozoa: A Colour Guide)




Figure 4 (corresponds to Figure 195 on page 98 of Free-Living Freshwater Protozoa: A Colour Guide)




Figure 5 (corresponds to Figure 192 on page 98 of Free-Living Freshwater Protozoa: A Colour Guide)




Figure 6 (corresponds to Figure 231 on page 129 of Freshwater Algae: Their Microscopic World Explored)