It doesn&#x27;t seem to talk about the plausible explanation that the <i>ratio</i> (of brain mass to body) also matters. So elephants have a bigger one but also loses a lot of its processing power to a greater number of neural signals (which probably increase linearly with weight).<p>According to this page, humans have the highest ratio except for a few species that have very small brains in absolute size, which probably miss out on benefits to scale.<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Brain-to-body_mass_ratio#Comparisons_between_groups" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Brain-to-body_mass_ratio#Compa...</a><p>I would also suggest that they&#x27;re very disadvantaged in not having developed the tools for more wide scale intergenerstional transmission of cultural knowledge.