Trophic Interaction
ENVR 1401: Environmental Science
Assignment #2
Assignment needs to be typed
List everything you consumed during one day (you will need to turn in this list to me with this assignment!)—breakfast, lunch, dinner, snacks, and beverages. After creating a list of food consumed,
label each item as from a producer, a primary consumer (e.g., cow), or secondary or higher consumer
(e.g., fish). If the food item contains both producers and consumers, note both and guess approximately
how much of each it contains. From the list, determine the approximate percentage of food obtained from
producers and the approximate percentage of food obtained from consumers. Determine from which
trophic level you eat. (The lowest trophic level will be secondary.) How much support do you receive
from the first trophic level? How much support from the second trophic level? How much support from
each remaining trophic level? If you ate more producers, how would this change the percentage of the
biomass pyramid necessary to support your survival? If you ate more food from secondary consumers
(fish), how would this change the percentage of the biomass pyramid necessary to support your survival?
EXAMPLE: This is only a guide to help you with what you need to do for this assignment.
A sample daily diet is given below based upon an ovo-lacto vegetarian diet. I eat from the first and
second trophic levels. Using only the item source frequency, not the quantity of food consumed, 67%
(8/12) of my diet comes directly from producers and 33% (4/12) comes from primary consumers. I eat
mainly from the first trophic level. If I ate more food from producers, the percentage of the biomass
pyramid necessary to support my survival would decrease. If I ate more food from secondary consumers,
the percentage of the biomass pyramid necessary to support me would increase.