Table 1.

Allometric equations for the scaling of organ masses and metabolic rates in mammals

OrganOrgan massSMROrgan mass×SMR
Liver0.033Mb0.872861Mb−0.2794.4Mb0.60
Brain0.011Mb0.761868Mb−0.1420.5Mb0.62
Kidneys0.007Mb0.852887Mb−0.0820.2Mb0.77
Heart0.006Mb0.983725Mb−0.1222.4Mb0.86
Remainder0.939Mb1.01125Mb−0.17117.4Mb0.84
  • Data taken from Wang et al. (2001).

    Mb, body mass in kg; SMR, specific metabolic rates in kJ kg−1 day−1.

    These relationships raise the question of why organs masses and specific metabolic rates decline with increasing body mass.