Many people assume most ecosystems are examples of a bottom up regulated system: that the primary producers, physical and chemical factors are what maintain the entire ecosystem and ensure the life of the consumers by controlling the ecosystem structure. Silliman and Bertness’ paper explains how this rule is applied too frequently, especially in salt marshes. In their paper they created an experiment to prove the existence of a strong top down consumer consumer amongst Littoraria (a type of sea snail) and Spartina (cordgrass) in southeastern coasts of the US.
Through the research done in their scientific experiment they have also shown the impact of eliminating a predator from its ecosystem may “indirectly alter the structure and function of intertidal marsh habitats.” This means their are also implications we have to be aware of when we kill predators for food or build on a natural ecosystem, kicking predators out of their habitats. Even though we think we may not be disrupting primary producers a lot of these ecosystems are actually top down regulated.
It’s interesting to see how they created a hypothesis that not only went against a common theory but actually completely contradicted one in many circumstances. This article opened up a new perspective to me and made me question other ecosystems which may come up more frequently in my other classes. Often we see things as a bottom up regulated system such as our food. But if we were to apply this to the human ecosystem do you think that it could be perceived as bottom up or as top down in terms of what organisms we depend on for survival? What about within the education ecosystem?
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