Final answer:
The claim that the resting metabolic rate in mammals is given by M=0.8B^3/4 is false. The actual relationship is an allometric one and varies with several factors such as age, gender, and overall muscle mass.
Step-by-step explanation:
The statement in the question is false. In mammals, the resting metabolic rate (M) is related to body mass (B) according to an allometric equation, which is often approximated as M = k · B3/4, wherein k is a proportionality constant. This relationship is known as Kleiber's law. However, the basal metabolic rate (BMR) is not simply represented as M=0.8B3/4. BMR varies with body size, age, gender, and muscle mass. Generally, larger mammals have a higher total BMR but a lower BMR per unit body weight, since smaller animals require more energy relative to their size to maintain homeostasis. The BMR is the minimum energy required for vital functions such as maintaining the heart rate, respiration, and kidney function at rest.