User blog:StaraptorEmpoleon/Monotypic vs. polytypic

So, what do these two words mean?

Polytypic: having several different taxa of the next lower rank, especially having several subspecies.

Monotypic: a taxon which only contains one member of the next lesser rank, such as an order which contains a single family.

Examples of poltypism

 * Order: Passeriformes (passerines)
 * Family: Emberizidae (emberizids)
 * Genus: Junco (juncos)
 * Species: Junco hyemalis (dark-eyed junco)

The dark-eyed junco has at least fifteen subspecies, but they be proven to be separate species.

Examples of monotypism

 * Order: Coliiformes (mousebirds)
 * Family: Leptosomidae (cuckoo-roller)
 * Genus: Sagittarius (secretarybird)
 * Species: Sagittarius serpentarius (secretarybird)

The secretarybird has no subspecies; while the mousebirds' order only has one family, but it has two genera which makes in polytypic; cuckoo-roller's family is monotypic; the secretarybird's genus and species is monotypic as well.