Paraphyly in species Paraphyly

species have special status in systematics being observable feature of nature , basic unit of classification. phylogenetic species concept requires species monophyletic, paraphyletic species common in nature. paraphyly common in speciation, whereby mother species (a paraspecies) gives rise daughter species without becoming extinct. research indicates many 20 percent of animal species , between 20 , 50 percent of plant species paraphyletic. accounting these facts, taxonomists argue paraphyly trait of nature should acknowledged @ higher taxonomic levels. others argue retain monophyly in higher taxa, special status of species should excuse them monophyly prerequisite.