Squirrel In Action

Be that as it may, the three-way split of the main squirrel lineage is rather neat from a biogeographical and ecological perspective. Two of the three subfamilies are of about equal size, containing between nearly 70 to some 80 species each; the third is about twice as large. The Sciurinae contains arboreal (tree-living) squirrels, mainly of the Americas and to a lesser extent Eurasia. The Callosciurinae on the other hand is most diverse in tropical Asia and contains squirrels which are also arboreal, but have a markedly different habitus and appear more "elegant", an effect enhanced by their often very colorful fur. The Xerinae – the largest subfamily – are made up from the mainly terrestrial (ground-living) forms and include the large marmots and the popular prairie dogs among others, as well as the tree squirrels of Africa; they tend to be more gregarious than other squirrels which do not usually live together in close-knit groups.
• Basal and incertae sedis Sciuridae (all fossil)