Ecological Pyramids: graphs which illustrate the trophic levels in a community.

Most ecological pyramids are large at the base and narrow at the top. This is because every time that an organism is eaten by the next trophic level, some of the energy is lost as heat. More Energy Less Energy

3 TYPES OF PYRAMIDS: 1.Pyramid of Biomass 2.Pyramid of Energy 3.Pyramid of Numbers

Pyramid of Biomass: Illustrates the amount of biomass in each trophic level –Biomass weight is determined after dehydration Shows the amount of matter lost between trophic levels. Measured in Kg, grams or pounds

Pyramid of Biomass

Pyramid of Energy: Shows the energy available at each trophic level. –The size of the blocks represents the proportion of productivity –Measured in Joules or Calories

Pyramid of Energy: Most of the energy available to the community is in the 1st trophic level. Only 10-20% of the energy is available to the next trophic level (≈ 90% lost)

Pyramid of Numbers: Illustration of the number of organisms at each level

What kind of Pyramid is this? Energy, the trophic levels are measured in Kilocalories

How can more people be supported on Earth when there is a limited supply of resources? Human Population Growth It depends on what they are eating…

The End or is it just the beginning…