Energy Flows Down a One Way Street

Energy is transferred through a food chain in a "one way" direction.  It is passed from tropic level to trophic level and from one organism to another depending on what eats what.  I took some pictures out side my window and at the local park to show a simple food chain.

The first trophic level of a food chain is made of "producers".  Producers, like the trees and grass in this photo, are known as "autotrophs" as they can automatically make their own food through the process of photosynthesis in which they will capture solar energy and convert it into the energy they need to sustain life.  I was able to take this lovely spring shot out at Mark Twain National Forrest.  If you have not seen this place for yourself, you should really visit it.  It is a beautiful place to spend an afternoon just relaxing with the family.










The second trophic level of a food chain consists of only herbivores.  Those organisms like the humming bird pictured here and other birds I find in my yard will eat seeds and the nectar from flowers.  They are know as hetertrophs and are primary consumers.  They must rely on eating something else to obtain energy.













The third trophic level, also know as secondary consumers as they are typically the second in the food chain to eat, are also heterotrophs.  This cat was after something and getting ready to pounce.  I don't know if he saw the hummingbird too, or if it was an insect that caught his eye.  Either way, he needs to consume an outside source of food to obtain energy.


All of the energy transferred within a food chain ultimately comes from the sun.  Each organism along the chain used what it can and only passes on about 10% of the original energy to the next level.  I encourage you all to look around and see what you can find to be a possible food chain right in your own yard.