The dodo, a bird we hardly know

The most famous bird in Mauritius is also one of the least understood. For all its renown, surprisingly little is known about this large flightless bird. The reason is chronological: it was described, then wiped out, before the modern science of describing species had been established. Everything written since therefore comes from bones, a handful of sailors’ accounts and a single relic of flesh.

The dodo was a pigeon. Genetics points to the Nicobar pigeon, a bird of South-East Asia, as its closest living relative. This is no mere quirk of classification: it places the dodo in a family of strong fliers, one member of which, isolated on an island without land predators, lost the use of flight.

Its appearance was not what we imagine. The most recent work depicts a bird slimmer and more upright than the one in the engravings, standing about 70 centimetres tall and probably weighing around 12 kilograms. The dazed, obese creature of the old illustrations is not what the bones describe. Seventy centimetres and a dozen kilograms: a large bird, and in no way a caricature.

Its diet can be read in the fossils. The presence of a large gizzard stone, which aids digestion, points to a diet of fallen fruit and seeds. The detail matters beyond the bird itself: the dodo could swallow large seeds, and since its disappearance, large-seeded plants have been less well dispersed by animals. The extinction of a bird leaves a hole in the workings of a forest.

This is one of the most misunderstood points. No taxidermy specimen has survived: every dodo seen in a museum is a reconstruction. There are only two near-complete skeletons in the world whose bones all come from a single individual, and another, less complete, in Durban. Everything else is either an assemblage of bones from several birds, or a model.

The one exception is in Oxford. The Oxford University Museum of Natural History holds what remains of the so-called Tradescant dodo: a skull bearing the left side of the skin, the sclerotic ring of the eye, the skeleton of a foot, a sectioned femur, a feather taken from the head in 1986, and various tissue samples taken over the years. No one knows how the Tradescant family came by this specimen, nor how much of the original bird it represented. It first appears in a 1656 catalogue of the Tradescant collection, which describes it in a single line: a dodar, from the island of Mauritius, unable to fly because it was too big. That collection is one of the founding collections of the Ashmolean Museum.

This mummified skin from the head is the only dodo soft tissue available to DNA research. It has also revealed, for the first time, how this individual died: shot in the back of the head.

The last reliable sighting dates from 1662, and the bird may have survived until 1680. The cause lies first with introduced animals, pigs and rats: they did not merely kill the birds, they probably ate their eggs as well.

This is the most useful correction to make to the popular story. The dodo was not eaten down to the last bird by starving sailors who had only to bend down. A bird that lays its eggs on the ground, on an island where pigs and rats are being landed, loses its offspring before it loses its adults.

A great deal, in truth. The number of individuals, the species’ distribution across the island, its social behaviour, the length of its decline: all of this remains unknown. As for de-extinction projects, the one led by the company Colossal is disputed.

What remains, then, is a bird whose approximate size, probable diet and relatives are known, along with the rough date of the last encounter. That is little for a national symbol. It is already a great deal for an animal extinct for more than three centuries, of which nothing survives in the way of flesh but a head and a foot.

Travellers will nonetheless meet it everywhere in Mauritius, as an emblem, a silhouette, a souvenir. They will now know that this rotund silhouette belongs to the engravings and not to the bird: a pigeon 70 centimetres tall, slender and upright, an eater of fallen fruit and seeds, which the island lost with the arrival of people and their animals.