Organisms with high metabolic rates often have inefficient energy production due to unsaturated fats in their membranes.

“then I also mentioned permeability to other ions like sodium and potassium and the sodium and pottassium gradient is also incredibly important to be maintained between the intracellular and extracellular space and so when we're leaking the sodium and potassium through we then have to waste a bunch of ATP pumping that back and maintaining that gradient and these two things together account for a massive shift in the efficiency of energy production when we have more polyunsaturated fats versus less polyunsaturated fats”

“but then I also mentioned permeability to other ions like sodium and potassium and the sodium and potassium gradient is also incredibly important to be maintained between the intracellular and extracellular space and so when we're leaking the sodium and potassium through we then have to waste a bunch of ATP pumping that back and maintaining that gradient and these two things together account for a massive shift in the efficiency of energy production when we have more polyunsaturated fats versus less polyunsaturated fats”