In a food pyramid, there is typically less biomass
In a food pyramid or ecological pyramid, there is typically less biomass as you move up the trophic levels. This means that there is a decrease in the amount of organic matter or living organisms as you move from the producer (plants) to the primary consumers (herbivores) to the secondary consumers (predators).
The reason for this decrease in biomass can be attributed to the concept of energy transfer and efficiency. At each trophic level, organisms obtain energy by consuming the organisms at the lower trophic level. However, not all of the energy from the consumed organisms is transferred or assimilated by the consumer. There is a loss of energy as heat during metabolism, excretion, and respiration.
Additionally, higher trophic levels require more energy to sustain their activities and physiological functions. As a result, there is a decrease in biomass due to the limited availability of energy and the inefficiency in energy transfer between trophic levels. This is indicated by the diminishing size of the bars in a food pyramid as they move up from producers to consumers.