For humans, there is only one living species: Homo sapiens. However, in past ages other species, such as Homo erectus , may have coexisted with Homo sapiens. Homo erectus is considered a separate species because presumably it could not mate with Homo sapiens. The classification scheme provides a mechanism for bringing together various species into progressively larger groups. Taxonomists classify two species together in the same genus (the plural is genera ). For example, the horse Equus caballus and the donkey Equus assinus are both placed in the genus Equus . Similar genera are brought together to form a family. Similar families are classified within an order. Orders with similar characteristics are grouped in a class. Related classes are grouped together as divisions or phyla (the singular is phylum ). Divisions are used for plants and fungi, while phyla are used for animals and animal-like organisms. The largest and broadest
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 11/11/2011 for the course BIO 101 taught by Professor Pesthy during the Fall '07 term at Texas State.