Electronic supplementary material Table S1. List of mammals used in this study This table includes the species name, Kyoto Encyclopedia of Genes and Genomes (KEGG) organism identifier (see www.genome.jp/kegg/catalog/org_list.html), body mass [g], mass-specific metabolic rate [W/g], genome size (i.e., the number of base pairs), number of protein-encoding genes, number of genes in each functional category [count]. (XLSX) Table S2. Correlation between NOGF and body size for all functional categories in which PICs were not considered See Table 1 for the description of table elements. (XLSX) Table S3. Correlation between NOGF and body size for all functional categories in which PICs were considered See table 1 for description of table elements. (XLSX) Figure S1. Phylogenetic tree of the 32 mammals used in this study. The node labels correspond to the KEGG organism identifier. The tree presented in the Newick format is as follows: (((((mmu:0.08104,rno:0.08248):0.04951,cge:0.12476):0.05344,ngi:0.11493):0.03966,(hgl:0.14409,(ocu:0.14687,(tup:0.13074,(((((((hsa:0.00253,ptr:0.00570):0.00045,ggo:0.00678):0.00389,pon:0.01198):0.00043,nle:0.01098):0.00529,mcc:0.02861):0.01593,cjc:0.04209):0.04991,(((((aml:0.00719,umr:0.00536):0.02221,cfa:0.03616):0.01115,(fca:0.00893,ptg:0.00972):0.03536):0.03039,((((((chx:0.01017,oas:0.00724):0.00583,phd:0.00768):0.01267,bta:0.02947):0.04670,(bacu:0.01987,lve:0.02461):0.02658):0.01069,ssc:0.07818):0.00211,cfr:0.07260):0.01699):0.00196,(myb:0.10819,(ecb:0.07922,pale:0.06770):0.00146):0.00192):0.02142):0.00257):0.00987):0.00324):0.02469):0.08808,(mdo:0.10233,shr:0.10678):0.13721). (DOCX)