According to David Steadman, from the Florida Museum of Natural History, “Pigeons and doves just plain taste good.” And no, that’s not his taste in meals, but it does help explain why the just-discovered giant pigeon Tongoenas burleyi went extinct on the island of Tonga soon after people arrived.
Steadman found fossils of the pigeon, which measured about 20 inches long and weighed at least five times as much as today’s city-dwelling pigeons, in a cave on the Tongan island of ‘Eua. “I said, ‘Oh my God, I’ve never seen a pigeon that big,'” he said. “It was clearly something different.”
So he enlisted the help of archaeologist David Burley from Simon Fraser University to excavate the site. The two unearthed charred remains of T. burleyi (yes, it was named after Burley), which showed that the birds were cooked and eaten.
The team, along with Oona Takano, a doctoral student at the University of New Mexico, determined that T. burleyi thrived on ‘Eua for about 60,000 years. Then, humans arrived just under 3,000 years ago, and the bird vanished.
To the Extreme
While we’ll never know just how the big bird tasted, we do know what it ate: large fruits from trees in the guava, mango, and chinaberry families. The researchers say that the bird was probably able to swallow fruit as big as a tennis ball, which allowed it to spread the seeds of these larger fruit trees around the Tongan islands through their feces. The birds likely evolved in concert with the trees, in an example of what’s known as co-evolution.
“Some of these trees have big, fleshy fruit, clearly adapted for a big pigeon to gulp whole and pass the seeds,” Steadman said. “Of the fruit-eating pigeons, this bird is the largest and could have gulped bigger canopy fruit than any others. It takes co-evolution to the extreme.”
Joining the Dodo
T. burleyi is not the first Pacific Island giant pigeon to go extinct from man’s appetite. The dodo, the Kanaka pigeon from Tonga, and the Viti Levu pigeon of Fiji were also hunted to extinction.
Now that this pigeon—whose discovery has added an entirely new genus and species to avian taxonomy—is also extinct, local flora might take a hit.
“T. burleyi provided an important service by moving seeds to other islands,” said Takano. “The pigeon species on Tonga today are too small to eat large fruits, which imperils certain fruit trees.”
The research has been reported in Biotaxa.