TY - DATA T1 - Supplementary Material for: Cellular Scaling Rules for the Brains of Marsupials: Not as “Primitive” as Expected PY - 2017/07/25 AU - Dos Santos S.E. AU - Porfirio J. AU - da Cunha F.B. AU - Manger P.R. AU - Tavares W. AU - Pessoa L. AU - Raghanti M.A. AU - Sherwood C.C. AU - Herculano-Houzel S. UR - https://karger.figshare.com/articles/journal_contribution/Supplementary_Material_for_Cellular_Scaling_Rules_for_the_Brains_of_Marsupials_Not_as_Primitive_as_Expected/4588471 DO - 10.6084/m9.figshare.4588471.v2 L4 - https://karger.figshare.com/ndownloader/files/7428178 L4 - https://karger.figshare.com/ndownloader/files/7428181 L4 - https://karger.figshare.com/ndownloader/files/7428184 L4 - https://karger.figshare.com/ndownloader/files/7428187 L4 - https://karger.figshare.com/ndownloader/files/7428190 L4 - https://karger.figshare.com/ndownloader/files/7428193 L4 - https://karger.figshare.com/ndownloader/files/7428196 L4 - https://karger.figshare.com/ndownloader/files/7428199 L4 - https://karger.figshare.com/ndownloader/files/7428205 L4 - https://karger.figshare.com/ndownloader/files/7428211 L4 - https://karger.figshare.com/ndownloader/files/7428214 L4 - https://karger.figshare.com/ndownloader/files/8957056 KW - Evolution KW - Allometry KW - Marsupials KW - Brain size KW - Numbers of neurons KW - Glia/neuron ratio KW - Cortical expansion N2 - In the effort to understand the evolution of mammalian brains, we have found that common relationships between brain structure mass and numbers of nonneuronal (glial and vascular) cells apply across eutherian mammals, but brain structure mass scales differently with numbers of neurons across structures and across primate and nonprimate clades. This suggests that the ancestral scaling rules for mammalian brains are those shared by extant nonprimate eutherians - but do these scaling relationships apply to marsupials, a sister group to eutherians that diverged early in mammalian evolution? Here we examine the cellular composition of the brains of 10 species of marsupials. We show that brain structure mass scales with numbers of nonneuronal cells, and numbers of cerebellar neurons scale with numbers of cerebral cortical neurons, comparable to what we have found in eutherians. These shared scaling relationships are therefore indicative of mechanisms that have been conserved since the first therians. In contrast, while marsupials share with nonprimate eutherians the scaling of cerebral cortex mass with number of neurons, their cerebella have more neurons than nonprimate eutherian cerebella of a similar mass, and their rest of brain has fewer neurons than eutherian structures of a similar mass. Moreover, Australasian marsupials exhibit ratios of neurons in the cerebral cortex and cerebellum over the rest of the brain, comparable to artiodactyls and primates. Our results suggest that Australasian marsupials have diverged from the ancestral Theria neuronal scaling rules, and support the suggestion that the scaling of average neuronal cell size with increasing numbers of neurons varies in evolution independently of the allocation of neurons across structures. ER -