Simplify the following text for a Grade 12 native English-speaking person.
Original: Although called treeshrews , they are not true shrews ( although they were previously classified in the Insectivora ) , and not all species are necessarily arboreal .
Simplified: Although called treeshrews , they are not true shrews ( although they were previously classified in the Insectivora ) , and are not all arboreal .