Approximately 8 million years ago, the small volcanic island of Mauritius formed in the Indian Ocean. The first published record of the bird dates to , a year after the Dutch claimed Mauritius, turning the island into a port of call and, later, a settlement.
Sometime during the second half of the 17th century—the exact date is unknown—the last dodo took its last breath. At the time, the concept of extinction—the notion that an entire species could vanish with no possibility of return—had not yet been developed, nor had advanced taxidermy techniques, and few good dodo specimens survived. The scarcity of physical evidence, combined with unreliable descriptions and fanciful illustrations of the birds, allowed myths and misconceptions to take root.
A Mauritian barber and amateur naturalist named Louis Etienne Thirioux found the skeleton in the early 20th century, but the specimen, currently housed by the Mauritius Institute in Port Louis, Mauritius, received little scientific scrutiny.
They used a 3-D laser scanner to produce high-resolution images of each bone, later reassembling these images into a three-dimensional, digital model of the skeleton. The team also scanned and modeled a second skeleton discovered by Thirioux, which is composed of the bones of at least two different dodos. Their findings were published in a special issue of the Journal of Vertebrate Paleontology in March. The extinction of the dodo was not simply a matter of systematic extermination. Our species created a major ecological disruption that many unique island species could nope cope with.
Still, the fact that dodos were regularly hunted and killed greatly contributed to their demise, and, contrary to the common belief that they had a disgusting flavor, Jan Den Hengst has drawn on several historical sources to show that dodo meat was considered to be quite palatable by sailors.
Who knows how many dodos were killed to satisfy gustatory curiosity? The Dutch who stayed on Mauritius observed the dodos, made notes about them, sketched them, and even brought stuffed dodos back to Europe, so why, then, are there so many inaccurate restorations?
The Age of Exploration both discovered and wiped out the dodo — from a geological perspective, it popped out of existence only yesterday — and so it is puzzling why an animal that died out so recently has been so poorly represented. In many cases, mistakes about the dodo are copycat errors.
One artist got something wrong and the mistake stuck. Take the color of the dodos, for example. First-hand accounts of the birds agreed that they sported plumage that was black to grey in color, but many 17th century Dutch paintings restored them as white. Whatever the reason, light-colored dodos stuck around. A single painting by Roelandt Savery had an even stronger effect. His rendition of the dodo, created around , differed from earlier drawings of dodos as long-legged and spry in showing the dodo as a fat, stumpy bird.
There are only two confirmed accounts of live dodos that were displayed in Europe, and Savery probably never saw a still-breathing dodo. Most artists who illustrated the bird had not seen a living specimen.
This situation left at least one tell-tale sign in artistic renderings of the bird — the enlarged nostrils. Sketches of live and recently-deceased birds show the nostrils as being very small, but in skeletons and stuffed specimens the soft tissue was gone, leaving the nasal cavity open and looking relatively large.
If a dodo restoration has large gaping nostrils, then it was based upon a long-dead specimen. Mistakes about dodo anatomy gained a cultural inertia that was difficult to stop. Extensively reviewed by dodo-expert Julian Hume in , illustrations of dodos were based on scrappy remnants and the works of others.
Strangely, though, the dodo became an almost mythical creature as soon as it became extinct. To some 18th century naturalists, the dodo was about as real as a griffin, and there seemed to be no conclusive evidence that the bird had ever actually existed.
Given that the French took control of Mauritius in and found no sign of the dodos, it seemed possible that the birds were the product of exaggeration and overactive imaginations. It was only in the early 19th century, when European naturalists began describing dodo scraps scattered among various museums, that it became widely recognized as a real animal that had recently gone extinct at the hands of our species.
Scientists working today know more about the dodo than the naturalists who overlapped in time with the last birds, although much about this strange bird remains uncertain. Among the frustratingly fuzzy questions about the dodo was how much it weighed. The dodo was endemic to the island of Mauritius, miles from the Eastern coast of Madagascar. The dodo was primarily a forest bird, occasionally venturing closer to the shoreline.
More than 26 million years ago, these pigeon-like birds found paradise while exploring the Indian Ocean: the Mascarene Islands. With abundant food and no predators, the birds had no reason to leave. And so, over the years their descendants slowly grew bigger and heavier, their beaks grew larger, their wings smaller: dodos evolved. When did the dodo go extinct? Until recently, the last confirmed dodo sighting on its home island of Mauritius was made in , but a estimate by David Roberts and Andrew Solow placed the extinction of the bird around Why did the dodo became extinct?
The dodo had no natural enemies on Mauritius. Life was sweet for dodos until humans also discovered the Mascarenes, in the late s. Despite the fact that humans were far bigger then them, dodos were not afraid of these intruders. Fearless and flightless, they were an easy prey. It takes a lot of energy to maintain powered flight, which is why nature favors this adaptation only when it's absolutely necessary. After the dodo bird's pigeon ancestors landed on their island paradise, they gradually lost their ability to fly, at the same time evolving to turkey-like sizes.
Secondary flightlessness is a recurrent theme in bird evolution and has been observed in penguins, ostriches, and chickens, not to mention the terror birds that preyed on South American mammals only a few million years after the dinosaurs went extinct.
Evolution is a conservative process: A given animal will produce only as many young as is strictly necessary to propagate the species. Because the dodo bird had no natural enemies, females enjoyed the luxury of laying only one egg at a time. Most other birds lay multiple eggs in order to increase the odds of at least one egg hatching, escaping predators or natural disaster, and actually surviving. This one-egg-per-dodo-bird policy had disastrous consequences when the macaques owned by Dutch settlers learned how to raid dodo nests, and the cats, rats, and pigs that invariably got loose from ships went feral and preyed on the chicks.
Ironically, considering how indiscriminately they were clubbed to death by Dutch settlers, dodo birds weren't all that tasty.
Dining options being fairly limited in the 17th century, though, the sailors who landed on Mauritius did the best with what they had, eating as much of the clubbed dodo carcasses as they could stomach and then preserving the leftovers with salt. There's no particular reason the meat of the dodo would have been unsavory to human beings; after all, this bird subsisted on the tasty fruits, nuts, and roots native to Mauritius and possibly shellfish. Just to show what an anomaly the dodo bird was, genetic analysis of preserved specimens has confirmed that its closest living relative is the Nicobar pigeon, a much smaller flying bird that ranges across the southern Pacific.
Another relative, now extinct, was the Rodrigues solitaire, which occupied the Indian island ocean of Rodrigues and suffered the same fate as its more famous cousin. Like the dodo, the Rodrigues solitaire laid only one egg at a time, and it was completely unprepared for the human settlers that landed on its island in the 17th century. There was only a short interval between the "official" naming of the dodo bird and its disappearance—but an awful lot of confusion was generated during those 64 years.
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