Comparison of mitochondrial cytochrome b and 12S rRNA sequences isolated from a dodo tarsal and a Rodrigues solitaire femur supported their close relationship and their placement within the family of pigeons and doves Columbidae.
The genetic evidence was interpreted as suggesting the Southeast Asian Nicobar pigeon (Caloenas nicobarica) to be their closest living relative among 35 analyzed species of pigeons and doves, followed by the crowned pigeons (genus Goura) of New Guinea and the superficially dodo-like tooth-billed pigeon from Samoa.
The genus of the latter is Didunculus ("little dodo"), and it was called "dodlet" by Richard Owen.
The following cladogram, from Shapiro and colleagues (2002), shows the position of the dodo and solitaire within the pigeon and dove family.

A similar cladogram was published in 2007, inverting the placement of Goura and Didunculus and including the pheasant pigeon and the thick-billed ground pigeon at the base of the clade.
Based on behavioural and morphological evidence, Jolyon C. Parish proposed that the dodo and Rodrigues solitaire should be placed in the Gourinae subfamily along with the Goura pigeons and others, in agreement with the genetic evidence.
In 2014, DNA of the only known specimen of the recently extinct spotted green pigeon (Caloenas maculata) was analysed, and it was found to be a close relative of the Nicobar pigeon, and thus also the dodo and Rodrigues solitaire.

For many years the dodo and the Rodrigues solitaire were placed in a family of their own, the Raphidae (formerly Dididae), because their exact relationships with other pigeons were unresolved.
Each was placed in its own monotypic family (Raphidae and Pezophapidae, respectively), as it was thought that they had evolved their similar features independently.
Osteological and molecular data has since led to the dissolution of the family Raphidae, and the dodo and solitaire are now placed in their own subfamily, Raphinae, in the family Columbidae.

The "Réunion solitaire", long considered a third extinct didine bird, has turned out to be an ibis; it is now known as Threskiornis solitarius.
Comparison of mitochondrial cytochrome b and 12S rRNA sequences isolated from a dodo tarsal and a Rodrigues solitaire femur supported their close relationship and their placement within the family of pigeons and doves Columbidae. The genetic evidence was interpreted as suggesting the Southeast Asian Nicobar pigeon (Caloenas nicobarica) to be their closest living relative among 35 analyzed species of pigeons and doves, followed by the crowned pigeons (genus Goura) of New Guinea and the superficially dodo-like tooth-billed pigeon from Samoa. The genus of the latter is Didunculus ("little dodo"), and it was called "dodlet" by Richard Owen. The following cladogram, from Shapiro and colleagues (2002), shows the position of the dodo and solitaire within the pigeon and dove family.
A similar cladogram was published in 2007, inverting the placement of Goura and Didunculus and including the pheasant pigeon and the thick-billed ground pigeon at the base of the clade. Based on behavioural and morphological evidence, Jolyon C. Parish proposed that the dodo and Rodrigues solitaire should be placed in the Gourinae subfamily along with the Goura pigeons and others, in agreement with the genetic evidence. In 2014, DNA of the only known specimen of the recently extinct spotted green pigeon (Caloenas maculata) was analysed, and it was found to be a close relative of the Nicobar pigeon, and thus also the dodo and Rodrigues solitaire.
For many years the dodo and the Rodrigues solitaire were placed in a family of their own, the Raphidae (formerly Dididae), because their exact relationships with other pigeons were unresolved. Each was placed in its own monotypic family (Raphidae and Pezophapidae, respectively), as it was thought that they had evolved their similar features independently. Osteological and molecular data has since led to the dissolution of the family Raphidae, and the dodo and solitaire are now placed in their own subfamily, Raphinae, in the family Columbidae.
The "Réunion solitaire", long considered a third extinct didine bird, has turned out to be an ibis; it is now known as Threskiornis solitarius.
Raphinae