the Mascarene Islands of Mauritius and Rodrigues, but became extinct through hunting by humans and predation by introduced non-native mammals following human colonisation in the 17th century. Historically, many different groups have been named for both the dodo and the Rodrigues solitaire, not all grouping them together. Most recently, it is considered that the two birds can be classified in Columbidae, often under the subfamily Raphinae. The first person to suggest a close affinity to the doves was Johannes Theodor Reinhardt, whose opinions were then supported by Hugh Edwin Strickland and Alexander Gordon Melville.
Recent extractions of DNA from the dodo and Rodrigues solitaire, as well as 37 species of doves, has found where in Columbidae the raphines should be placed. Surprisingly, raphines are not the most primitive columbid, instead they are grouped with the Nicobar pigeon as their closest relative, with other closely related birds being the crowned pigeons and tooth-billed pigeon. A third raphine, Raphus solitarius, is now considered to be an ibis in the genus Threskiornis.
Both the Rodrigues solitaire and the dodo are now extinct. A common threshold of the extinction of the dodo is 1662, but some possible sightings had been made as late as 1688. The last sighting with a description was in 1662, but a statistical analysis by Roberts and Solow found that the extinction of the dodo was in 1693. The Rodrigues solitaire was killed off later than the dodo. The IUCN uses an extinction date of 1778 for the solitaire, although a more probable date would be in the 1750s or 1760s. Both birds became extinct as a consequence of human hunting and the introduction of mammals that ate the birds and their eggs.
This clade is part of the order Columbiformes and contains the monotypic genera Pezophaps and Raphus. The former contains the species Pezophaps solitaria (the Rodrigues solitaire), the latter the dodo, Raphus cucullatus. These birds reached an impressive size as a result of isolation on islands free of predators, in accordance with Foster's rule.
Historically, the dodo was assigned the genus Didus, now a junior synonym of Raphus. In 1848, a new species within the now defunct genus Didus, D. nazarenus, was named by Hugh Edwin Strickland and Alexander Gordon Melville. To house their new species, as well as the other species known at the time, Strickland and Melville named the subfamily Didinae. In 1893 three species were assigned to the group Pezophaps solitarius, Didus ineptus, and the possible species Didus borbonicus. Today, only two raphine species are known, with Didus ineptus becoming a junior subjective synonym of Raphus cucullatus; Didus? borbonicus now classified as the ibis Threskiornis solitarius; and Didus nazarenus being identified as synonymous with Pezophaps solitarius.
A suborder named in 1893 by Sharpe, Didi was defined as a group including only the massive birds, that were sister to Columbidae, from the Mascarene Islands of Mauritius, Réunion, and Rodrigues. Features grouping Didi with Columbidae were the angle of the mandible and the hook at the end of the beak.
In 1811, Johann Karl Wilhelm Illiger created a new family for the genus Didus. He named the family Inepti, and in it included only Didus ineptus, now a synonym of Raphus cucullatus. Illiger concluded that the dodo was related to ostriches and rheas, and so placed Inepti in the order Rasores, as the sister family to Gallinacei, Epollicati (a defunct group including Turnix and Syrrhaptes]), Columbini , and Crypturi.]
In 1842, Johannes Theodor Reinhardt proposed they were ground doves, based on studies of a dodo skull he had rediscovered in the royal Danish collection of Copenhagen.This view was met with ridicule, but later supported by Strickland and Melville, who suggested the common descent of the Rodrigues solitaire and the dodo in 1848, after dissecting the only known dodo specimen with soft tissue and comparing it with the few solitaire remains then available. Strickland stated that although not identical, these birds shared many distinguishing features in the leg bones, features which were otherwise known only in pigeons.
The raphines are sometimes separated as a distinct family Raphidae, and their affinities were for long uncertain. They were initially placed in the ratites due to their peculiar, flightlessness-related apomorphies, and a relationship to the Rallidae has also been suggested. Osteological and molecular data, however, agrees that placement in the Columbidae is more appropriate. Many different affinities have historically been suggested for the dodo, including that it was a small ostrich, a rail, an albatross, or a vulture.