Mysterious Extinct Bird Species Descendants of 'Island Hoppers'

Two mysterious extinct bird species, the spotted green pigeon and its relative the dodo, according to scientists, are descendants from their "island hopping" ancestors, they reported in the journal BMC Evolutionary Biology.

The spotted green pigeon (Caloenas maculata) is a historically elusive species. The only known example is the Liverpool pigeon, which is currently in the city's World Museum, and the other known specimen is lost. There are no records of the bird in the wild, no one knows where it was found and scientists weren't even really sure if it was its own species - they thought it was just an unusual form of the Nicobar pigeon from around Indonesia.

But this recent study puts forth the theory that, based on spotted pigeon DNA, it is a descendant of "island hoppers" - birds that moved between islands around India and Southeast Asia.

"We are very pleased that the extinct spotted green pigeon has its correct place in the world of birds after more than 230 years," Clemency Fisher, Curator of Vertebrate Zoology at the World Museum, said in a press release.

The scientists took two feathers of the spotted green pigeon and analyzed small fragments of DNA, called "mini barcodes" - small sections of DNA which are unique for most bird species. They looked at these sections of the pigeon's DNA, and compared it to other species.

This showed that the spotted bird is indeed a separate species, showing a unique DNA barcode compared to other pigeons. Though, scientists were not wrong to assume that it might have been a form of Nicobar pigeon. Genetically speaking, that is its closest relative, along with the dodo and Rodrigues solitaire, both extinct birds from islands near Madagascar.

These individual species evolved after their island-hopping ancestors moved between islands before settling in once place. For instance, the dodo's ancestor managed to hop as far as the island of Mauritius near Madagascar where it then lost the ability to fly.

"This study improves our ability to identify novel species from historic remains, and also those that are not novel after all," added lead author Dr. Tim Heupink of Griffith University Australia. "Ultimately this will help us to measure and understand the extinction of local populations and entire species."