What is one major disadvantage in using the pyramid of biomass? What might an unhealthy pyramid of energy look like?

The main disadvantage with this type of  Pyramid is that it can make a tropic level appear to contain more energy than it actually does. The bones of an animal are often not eaten; nevertheless, it would still be quantified even though it does not contribute to the overall flow of energy into the next tropic level.  An unhealthy pyramid of energy would have more energy at the higher tropic levels than the lower tropic levels (inverted pyramid); thus, it would collapse.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.