In general, smaller animals tend to have larger brains, measured as a fraction of body size. For mammals, the relationship between brain volume and body mass essentially follows a power law with an exponent of about 0.75. This formula describes the central tendency, but every family of mammals departs from it to some degree, in a way that reflects in part the complexity of their behavior.
In general, smaller animals tend to have larger brains compared to their size. For mammals, the relationship between brain volume and body mass is described by a power law with an exponent of about 0.75. This formula captures the typical trend, but each mammal family exhibits variations in this relationship, which are linked to their behavioral complexity.