G.2.3 Discuss the difficulties of classifying organisms into trophic levels.
- Relationship of ecosystem goes further than just food chains and pyramid. A food web gives a true but complicated picture of what is being eaten in an ecosystem.
- It is difficult to classify organisms into trophic levels because one organism may be considered tertiary consumer when it is eating other carnivores, but a secondary consumer when it is eating an herbivore
ex) An eagle is a tertiary consumer when eating rattlesnakes but a secondary consumer when eating rabbits
- Another difficulty is where to put omnivores because they can become both primary consumers, secondary consumers, or tertiary consumers.
ex) Raccoons eat mice, bird eggs, fish, frogs, nuts and fruits.
http://www.jenningsk12.net/WE/peimann/Science/FoodChains/Foodchains.html
http://media.decentcomedy.com/2010/croc3.jpg
Comments (1)
Jay said
at 1:17 pm on Aug 24, 2010
Kyle; this looks like about 3 minutes of work :( Please provide definitions, provide an example food web; discuss named examples of organisms illustrating this ambiguity as well as examples of organisms showing clear trophic levels. Put your brain into it for learning man!