The dodo was variously declared a small
ostrich, a
rail, an
albatross, or a
vulture, by early scientists. In 1842, Danish zoologist
Johannes Theodor Reinhardt proposed that dodos were ground
pigeons, based on studies of a dodo skull he had discovered in the collection of the
Natural History Museum of Denmark. This view was met with ridicule, but was later supported by English naturalists
Hugh Edwin Strickland and
Alexander Gordon Melville in their 1848
monograph The Dodo and Its Kindred, which attempted to separate
myth from reality. After
dissecting the
preserved head and foot of the specimen at the
Oxford University Museum and comparing it with the few remains then available of the extinct
Rodrigues solitaire (
Pezophaps solitaria), they concluded that the two were closely related. Strickland stated that although not identical, these birds shared many distinguishing features of the leg bones, otherwise known only in pigeons. Strickland and Melville established that the dodo was
anatomically similar to pigeons in many features. They pointed to the very short
keratinous portion of the
beak, with its long, slender, naked basal part. Other pigeons also have bare skin around their eyes, almost reaching their beak, as in dodos. The forehead was high in relation to the beak, and the
nostril was located low on the middle of the beak and surrounded by skin, a combination of features shared only with pigeons. The legs of the dodo were generally more similar to those of
terrestrial pigeons than of other birds, both in their
scales and in their skeletal features. Depictions of the large
crop hinted at a relationship with pigeons, in which this feature is more developed than in other birds. Pigeons generally have very small
clutches, and the dodo is said to have laid a single egg. Like pigeons, the dodo lacked the
vomer and
septum of the nostrils, and it shared details in the
mandible, the
zygomatic bone, the
palate, and the
hallux. The dodo differed from other pigeons mainly in the small size of the wings and the large size of the beak in proportion to the rest of the
cranium. Based on solitaire remains, it is now a synonym of that species. Crude drawings of the
red rail of
Mauritius were also misinterpreted as dodo species;
Didus broeckii and
Didus herberti. 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 also placed in its own
monotypic family (Raphidae and Pezophapidae, respectively), as it was thought that they had
evolved their similarities independently.
Osteological and
DNA analysis has since led to the dissolution of the family Raphidae, and the dodo and solitaire are now placed in the columbid subfamily Raphinae and tribe Raphini, along with their closest relatives. In 2024, the new subtribe
Raphina was created to include only the dodo and the solitaire.
Evolution is the closest living relative of the dodo In 2002, American geneticist
Beth Shapiro and colleagues analysed the DNA of the dodo for the first time. Comparison of
mitochondrial
cytochrome b and 12S
rRNA sequences isolated from a
tarsal of the Oxford specimen and a
femur of a Rodrigues solitaire confirmed their close relationship and their placement within the Columbidae. The genetic evidence was interpreted as showing the Southeast Asian
Nicobar pigeon (
Caloenas nicobarica) to be their closest living relative, followed by the
crowned pigeons (
Goura) of
New Guinea, and the superficially dodo-like
tooth-billed pigeon (
Didunculus strigirostris) from
Samoa (its scientific name refers to its dodo-like beak). This
clade consists of generally ground-dwelling island endemic pigeons. The following
cladogram shows the dodo's closest relationships within the Columbidae, based on Shapiro and colleagues, 2002: }} of the Oxford specimen's foot, which has been used to sample
DNA for
genetic analyses A similar cladogram was published in 2007, inverting the placement of
Goura and
Didunculus and including the
pheasant pigeon (
Otidiphaps nobilis) and the
thick-billed ground pigeon (
Trugon terrestris) at the base of the clade. The DNA used in these studies was obtained from the Oxford specimen, and since this material is degraded, and no usable DNA has been extracted from subfossil remains, these findings still need to be independently verified. Based on behavioural and morphological evidence, Jolyon C. Parish proposed that the dodo and Rodrigues solitaire should be placed in the subfamily
Gourinae 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. The 2002 study indicated that the ancestors of the dodo and the solitaire diverged around the
Paleogene-
Neogene boundary, about 23.03 million years ago. The
Mascarene Islands (Mauritius,
Réunion, and
Rodrigues), are of
volcanic origin and are less than 10 million years old. Therefore, the ancestors of both birds probably remained capable of flight for a considerable time after the separation of their
lineage. The Nicobar and spotted green pigeon were placed at the base of a lineage leading to the Raphinae, which indicates the
flightless raphines had ancestors that were able to fly, were semi-terrestrial, and inhabited islands. This in turn supports the hypothesis that the ancestors of those birds reached the Mascarene islands by
island hopping from South Asia. Despite its divergent skull morphology and adaptations for larger size, many features of its skeleton remained similar to those of smaller, flying pigeons. Another large, flightless pigeon, the
Viti Levu giant pigeon (
Natunaornis gigoura), was described in 2001 from
subfossil material from
Fiji. It was only slightly smaller than the dodo and the solitaire, and it too is thought to have been related to the crowned pigeons.
Etymology One of the original names for the dodo was the Dutch "
Walghvoghel", first used in the journal of Dutch
Vice admiral Wybrand van Warwijck, who visited Mauritius during the Second Dutch Expedition to Indonesia in 1598.
Walghe means "tasteless", "insipid", or "sickly", and means "bird". The name was translated by Jakob Friedlib into German as
Walchstök or
Walchvögel. The original Dutch report titled
Waarachtige Beschryving was lost, but the English translation survived: Another account from that voyage, perhaps the first to mention the dodo, states that the Portuguese referred to them as penguins. The meaning may not have been derived from
penguin (the Portuguese referred to those birds as "
fotilicaios" at the time), but from
pinion, a reference to the small wings. This crew also called them "griff-eendt" and "kermisgans", in reference to
fowl fattened for the
Kermesse festival in
Amsterdam, which was held the day after they anchored on Mauritius. , showing a
broad-billed parrot, a
red rail, and a dodo The
etymology of the word
dodo is unclear. Some ascribe it to the Dutch word
dodoor for "sluggard", but it is more probably related to
Dodaars, which means either "fat-arse" or "knot-arse", referring to the knot of feathers on the hind end. The first record of the word
Dodaars is in Captain Willem Van West-Zanen's journal in 1602. The English writer
Sir Thomas Herbert was the first to use the word
dodo in print in his 1634
travelogue claiming it was referred to as such by the Portuguese, who had visited Mauritius in 1507. Another Englishman, Emmanuel Altham, had used the word in a 1628 letter in which he also claimed its origin was Portuguese. The name "dodar" was introduced into English at the same time as dodo, but was only used until the 18th century. As far as is known, the Portuguese never mentioned the bird. Nevertheless, some sources still state that the word
dodo derives from the
Portuguese word
doudo (currently
doido), meaning "fool" or "crazy". It has also been suggested that
dodo was an
onomatopoeic approximation of the bird's call, a two-note pigeon-like sound resembling "doo-doo". The Latin name
cucullatus ("hooded") was first used in 1635 by the Spanish Jesuit
Juan Eusebio Nieremberg as
Cygnus cucullatus, in reference to
Carolus Clusius's 1605 depiction of a dodo. In the
tenth edition of his 18th-century classic work
Systema Naturae, the Swedish naturalist
Carl Linnaeus used
cucullatus as the specific name, but combined it with the genus name
Struthio (ostrich).
Mathurin Jacques Brisson coined the genus name
Raphus (referring to the
bustards) in 1760, resulting in the current name
Raphus cucullatus. In 1766, Linnaeus coined the new binomial
Didus ineptus (meaning "inept dodo"). This has become a
synonym of the earlier name because of
nomenclatural priority. == Description ==