I appreciate the trophic level organization we explored today. I'm a "big-picture" person and so seeing how all the different species could be categorized according to larger trophic guilds, denoting their function in the food web, really helped me wrap my mind around the organization of the reef ecosystem. Or, in the least, one way to organize the ecosystem. That doesn't lessen the complexity of the system though, which is something that I've noticed across the ecosystems: just because there is a classification system doesn't mean there is suddenly a sharp, non-overlapping pattern. In this case, just because an organism is a benthic feeder doesn't mean it cannot be a secondary consumer motive, for instance.
The inverted biomass trophic pyramid structure of the ocean ecosystem is quite intriguing as well. I was used to thinking of the trophic pyramid, regardless of the ecosystem, as supported by plants, with that level being the largest because there were simply more plants. But I never thought about the foundational trophic group in terms of biomass, and that biomass of plants differed by ecosystems. In the rainforest, plants must grow lots of leaves and climb as high as possible to catch as much sunlight as possible, or else adapt to shady environments. They grow deep roots to draw up essential nutrients as well, since the well-drained soil is usually less fertile. In the ocean, algae has to do no such thing because it has what it needs: light and water. Instead, quick regeneration and lower energy requirements allows the relatively small plants to support the vast ocean system. This is amazing since the demand for energy isn't any less, with just as many, if not more, organisms vying for energy.
Speaking of competition, I was reading a journal article about how some types of coral become more aggressive when there are other coral competing in the area. If reality does indeed follow Darwin's principles of limited resources and potential for exponential population growth, how do algae compete with each other? Rainforest plants surely do, but how would they with that seemingly never-ending ocean?
After the analysis in class we were able to go to the mangroves, which was a little less interesting than snorkeling and definitely stinky. It was cool to see the zonation pattern I had read about, and just like the trophic guilds, this isn't set in stone. The guide explained the zonation and described each mangrove type, but as he did I noticed he was describing a white mangrove that was in front of the black mangrove. So I asked why that was so and he explained that the zonation pattern is general; a pattern often observed, not a rule. He also explained how the size of the island could affect the zonation. This particularly small island hindered more widespread growth of each species, since the salinity levels changed so much as you headed inland. As such, it was normal to see two different mangroves meld into each other instead of follow clear cut delineations.
After the mangroves I was soooo ready for snorkeling, and I have to say, when we got there I was a lot more confident about myself (sometimes I just have to prove I can do it to no one other than myself). This time I thought it would be more difficult: I didn't have flipper, didn't even have water shoes, and I was going to do it on my own. I remembered they told us not to go into the water barefoot, and after seeing a huge urchin on the last trip, I swam toward Rebecca, who was sun bathing on the boat, and asked if I could use her shoes. She let me, and I was ready to go. Thank God the current wasn't too strong! I saw so many things, especially at the mangrove. It was crazy; one area between mangroves separated by a channel seemed to be a traffic area, with all kinds of fishes moving from one mangrove cay to another. Migration and interaction! Woooot! Essential components of genetic diversity :) I saw so many juveniles as well, and I often swam within their school. It was the most amazing thing I have EVER experienced. From what I did experience, I really, really, REALLY, think I prefer aquatic environments and obvious organismal movement.
Victory!!!
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