Today was the last official day of lab observation for the botany term project. However, after the discoveries made in mine, it would be tough to throw out.
At first, the aquarium seemed just as bleak as it was last time, however, there is still much life to be found! While it's true that most of the previous organisms I had been seeing are now dead (such as the Cyclops sp.), many are still enjoying life in the tank (Rainis and Russell, 1996). Familiar organisms cited today were: Coleps sp. (Rainis and Russell 1996), Philodina sp. (Pennack 1953), Euchlanis sp.(Pennack 1953), Tachysoma sp (Patterson 1996), and Acanthinocystis sp. (Patterson 2003), the last of whom have probably doubled in amount, they're everywhere! I was able to observe Philodina sp. especially nicely today. It resembled a caterpillar in both appearance and gait as it walked along the stem of one of the plants in the tank (Pennack 1953). Additionally, I saw quite a few diatoms, though specific identification wasn't made. They were interesting. We have just learned in class about their silica composed cell wall and I find them to be beautiful creatures. The specimens I noted were long, tubular, rod-shaped, and green tinted. There were many connected together in a long chain.
Also, I think it should be noted that the water level in my was tank noticeably lower than in other times. I don't know if this is evaporation due to the recently activated heating system, or maybe it was knocked over. Regardless, I don't think it had an effect on the organisms in the tank. Since most of them are dead, it's unlikely there's much competition for resources. The dead organisms have seemed to have actually INCREASED resources in the tank, at least food wise. This is just my theory since I don;t know where the bacteria came from nor how long they'd been there, only that they were in and around dead skeletons and attracting plenty of predatory protista, ready to eat them. The bacteria and dead organisms they accompany were especially notable in the prongs and rhizobia of Fontanalis sp., which is particularly nasty and debris covered like the other green plants in the tank (McFarland 2013). Rhizobia, we learned in lab, are structures resembling roots that mosses use to secure themselves and obtain nutrients, as they lack proper vascular and rooting system common in higher plants. (Cook & McFarland 2013). This area was home to other (living) organisms as well, probably feeders themselves.
One concentrated area of bacteria was found gathered around what appeared to be a long hyphae. Dr. McFarland originally thought it to be a water mold or a slime mold, but this proved to be false. A true identification was never found, and we ended up lovingly naming it "Aquatic Hyphae". I've captured a video of it below.
You can see a steady movement within the hyphae, implying it is undivided and thus coencyctic (or lacking septa). Also, there are a couple of small organisms in the video hanging around the hyphae. The organism ere really attracted to it, and this leads my to hypothesize more. Perhaps the bacteria found around this hyphae are symbiotic with the Aquatic Hyphae and since the organisms in my tank eat the bacteria, the attraction of the organisms to the hyphae is purely to eat. The Aquatic Hyphae was very long, nearly the length of my whole tank and had several branches and turns. It's end was found to be in the debris of the bottom and therefore untraceable. The "nubs" protruding from the hyphae are unclear to us as well. Are they for reproduction? Who knows?
The Aquatic hyphae wasn't the only new organism sited today. Two Amoeba sp., differing drastically were noted as well (Patterson, 1996). One of which I've captured in Fig 1. It was later further identified as Amoeba centropyxs (Patterson 1996).
Fig. 1. Amoeba centropxys. shown with foot (Patterson 1996). |
Notice the little protruding foot, which it uses to move itself since it does't have cilia (Patterson, 1989). Both of the Amoeba sp. moved in a slow, slimy, sliding motions (Patterson 1996).The unpictured specimen looked like a typical cartoon depiction of a "germ". They were very interesting (as is everything). I have saved discussing growth of the Craspedacusta sp. for last (Pennack 1989). It was the first thing I went to upon viewing my tank and I had to pry myself away from it in order to properly take notes (I even came back after my chemistry class). It has definitely grown and has three defined polyps now, perhaps four. Excitingly, it has seems to have grown what appears to be a medusa!
Fig. 2. Craspedacusta sp. In the top left, a budding medusa protrudes (Pennack 1989). |
This means it is budding! Soon the medusa will detach.When it detaches it will grow into a young hyroid (jellyfish-like) organism that can be 2mm (Pennack 1989). The spawn of a medusa does not happen on every polyp and is instead sporadic/random (Pennack 1989). This is very fascinating and makes me feel special. The Craspedacusta sp. was very motionless (for the most part) yet again (Pennack 1989). However, using the dissecting microscope, which gave us a more defined picture, movement was noted (McFarland 2013). I also was able to see the cilia on one of the poms move in assumable response to Coleps sp. feeding on bacteria surround them (Rainis and Russell 1996). I am very curious as to why bacteria were swarming around the poms. They were also viewable inside the budding medusa. Curious. Dr. McFarland and Marisol (and myself) were very excited about the progression of the Craspedacusta sp. and its budding medusa (Pennack 1989). I believe I will be able to keep observing the tank until the end of the semester. This may be the end of the term project, but perhaps I will post more pictures of the Craspedacusta sp. if the tank is indeed kept for observation (Pennack 1989).