Developmental differences are correlated with relative brain size in birds: a comparative analysis (academic.oup.com)
MacLean, E. L., Barrickman, N. L., Johnson, E. M. & Wall, C. E. Sociality, ecology, and relative brain size in lemurs. (nature.com)
«If we use relative brain size as a metric of «intelligence» then one would have to conclude that dolphins are second in intelligence to modern humans,» Lori Marino, Lori Marino, a senior lecturer in neuroscience and behavioral biology at Emory University, told Discovery News. (seeker.com)