In a food pyramid there is typically less biomass at the top explain this phenomenon
The reason there is typically less biomass at the top of a food pyramid is because of the concept of energy transfer and efficiency. As energy moves up the food chain, it is lost at each level through various processes such as respiration, heat loss, and waste production.
At the base of the food pyramid are primary producers, such as plants, which are able to capture energy from the sun through photosynthesis. These producers convert sunlight into chemical energy, which is then transferred to herbivores that consume the plants. However, only a portion of the energy that the plants capture is actually transferred to the herbivores, as some is used for the plant's own growth and metabolism.
As the energy moves up the food chain to secondary consumers, such as carnivores that eat the herbivores, and then to tertiary consumers that eat the carnivores, there is less and less energy available. This is because each trophic level only retains about 10% of the energy from the level below it, with the rest being lost as heat or used for the organism's own metabolism.
This decrease in available energy at higher trophic levels results in less biomass being able to be supported at the top of the food pyramid. Therefore, there is typically less biomass at the top because there simply isn't enough energy available to support a large population of organisms at that level.