Friday, December 16, 2011

Papers

Hi all,
To my surprise it seemed that the second run of papers (coastal ecology) was generally worse than the first.  While this was not true in all cases, it was certainly a trend.  If any of you have any ideas why, I would love to hear them.  Are you tiring?  Is the proximity to break too great, too tempting?  I don't know, but I'd like to see a stronger finish.  To help I just sat down and wrote an example coastal ecology paper.  It is not perfect.  I did not edit it heavily or give it a second draft.  But, it should give you some ideas of the scope and sequence of an 'A' type paper.  Please note the parenthetical notations.  Most of you are not citing your papers or using references at all.  Presenting other people's ideas as your own is a form of Plagiarism (read: academic dishonesty).  I realize that you are just receiving proper instruction on these methods in your humanities classes now, but I plead with all of you to learn these techniques ASAP and to use them.  Colleges and Universities take plagiarism VERY seriously (and in my opinion, rightly so).  The paper should be followed by a Bibliography of all cited works.  It is too late and I'm too tired to do this right now, and I wanted to get this out to you to use as a resource.  I hope this is helpful to all of you.  Let me know if you have any questions.
Ciao!
Mr. H  

Coastal Ecology
Mr. Hatfield
               Coastal areas are abundant, productive habitats with a host of diverse and interesting ecological interactions.  Coastal areas are so productive because they have a stable temperature, a relatively constant supply of nutrients and, due to relatively shallow depths, an abundance of sunshine (Insert a reference here).  Plants and animals have existed in the shallows of the sea since the beginning of life itself. Therefore, evolution has had millions of years to find various states of equilibrium; although there is no doubt that evolution in these important areas has not run its course.  Competition, predation, desiccation, resource availability and human intervention are all providing important selection factors.
               The rocky intertidal is where the ocean meets land.  Any location where two ecosystems meet are usually important habitats for a diverse group of plants and animals.  These areas, called ecotones, have species from each distinct ecosystem, as well as animals that have adapted to live in the transition zone.  Nowhere is this more evident than on the sea stacks along the pacific coast.  Here, the ocean meets the land abruptly in dramatic fashion.  The tidal influences of the sun and moon bring the tides in and out twice each day, creating a dynamic and stressful environment for the species that make their home.  Because tides vary daily, and depending on the orientation of the sun, moon and earth to each other, there are several zones created in the rocky intertidal.  The top area, called the splash zone only gets water from the splashing of waves against the rock.  Below the splash zone is the intertidal zone, often broken up into the high tide, mid tide and low tide zones.  The high tide zone is only covered in the highest of tides, and the low tide zone is only exposed in the lowest of tides.  Below the low tide zone is the sub tidal area, which is never exposed to air.
               Because this environment is dynamic and productive, many different species have evolved to make their home here.  Two such species are the California Blue Mussel (CBM, Mytilus californianus, Phylum Mollusca) and the Ochre Sea Star (Pisaster ochraceous, Plylum Echinodermata).  These two species are in constant interaction with each other, and the elements.  The upper limits of M. californicus are determined by the tides, the lower limits are determined by predation from P. ochraceous.  As P. ochraceous do not have much in the way of predators (aside from an occasional otter) their only limit is desiccation.  Sea stars’ method of movement is hydraulic, depending on water pressure (i.e. without immersion in water, sea stars cannot move).    As such, CBMs are often found in a narrow band in the high tide zone.  However, when sea stars are removed from the system, CBMs disperse down into the mid and lower tide zones freely (Paine, 1974).  As CBM’s disperse lower in the intertidal, their density excludes other animals from the system, thus greatly reducing species diversity.  Moreover, as CBM’s are filter feeders, taking their nutrients out of suspension in the water, an increase in CBM density also decreases the availability of plankton and other nutrients to other species (Paine, 1974).  As such, the role of the sea star is greater than just keeping mussels in check, they are also helping to provide habitat and food for other species.  Because of this, Dr. Paine calls the sea star a keystone species, having a greater impact in their ecosystem and one might expect from their abundance alone.   
            A similar example of a predator maintaining a stable ecosystem is that of the sea otter (Phylum Vertebrata).  Otters’ favorite food is sea urchins (Phylum Echinodermata).  When otters are removed from an ecosystem, urchins run rampant and mow down the kelp forests found from California to Alaska (Estes and Duggins, 2005).  Without kelp forests, the ecosystem changes dramatically (Estes and Duggins, 2005) and eventually the urchin will run out of its food source.  So, while the otter does not directly eat the kelp, the presence of the otter in the ecosystem maintains a healthy balance of kelp and urchins.  Interestingly, the otter also depends directly on the kelp forests as they wrap themselves up in kelp while they sleep to prevent from floating away (insert reference).     
Another, and different dynamic system in the rocky intertidal is that of the nudibranch (Phylum Mollusca) and the sponge (Phylum Porifera).  The nudibranch is a sea slug, some species of which prey on sponges.  While this system is also a predator prey relationship, the outcome of the relationship is slightly different than that seen in the mussel/sea star interaction.  Here, because there are many different species of nudibranchs (insert number and reference here, its late and I’m feeling lazy), there has been intense competition for food resources (sponges) (Bloom, 1981).  This is particularly true since many sponges sequester their defense mechanisms from the food that they eat.  The evolutionary result of millions of years of competition has resulted is an ecological phenomena called resource partitioning; instead of competing against a superior competitor for the same resource, animals have evolved to seek a more available resource (in this case a different species of sponge) (Bloom, 1981).  Thus, some nudibranchs will only eat one species of sponge, even if another is more abundant in a given location (Bloom, 1981).   
               Humans are constantly affecting these environments and interactions as we struggle to find our ecological niche on planet earth.  We often vary between intense competitor/predator and savior.  Unfortunately for ecological balance, the bulk of our efforts manifest in the former.  This is particularly true in the case of the otter.  Otters were hunted intensely in the 1700s for their dense coats.  Otters were nearly hunted to extinction and the entire ecology of the west coast was changed.  Otters were extirpated from the coast of Oregon, and despite several efforts to reintroduce them here, they remain absent from our coast.  It is clear from ecological investigation that interactions are often delicate balances, but perhaps more importantly they evolved without the influence of human interaction.  While we are relatively new players in the ecological game, or impact is dramatic.  The scale at which we are creating change surpasses almost any other extinction event that the planet has seen.  Waking up to the impacts of our daily actions and decisions will be an important step in the evolution of our consciousness.  Whether we are up to it or not is yet to be determined.  If previous cultures are any indication, we may be in trouble (Diamond, 2005).

Bibliography:

Bloom 1981.  Resource Partitioning in Nudibranchs.  Oecologia, etc...
Diamond 2005.  Collapse, etc...
Paine 1974.  Pisaster...               

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