The clade Rhizaria has recently been proposed based on results from molecular systematics. Although its members vary greatly in morphology, DNA evidence suggests that rhizarians are a monophyletic group. Many species in Rhizaria are among the organisms referred to as amoebas. Amoebas were formerly defined as protists that move and feed by means of pseudopodia, extensions that may bulge from almost anywhere on the cell surface. An amoeba moves by extending a pseudopodium and anchoring the tip; more cytoplasm then streams into the pseudopodium. However, It is now clear that ameobas do not constitute a monophyletic group but are dispersed across many distantly related eukaryotic taxa.