April 24 (UPI) -- Researchers have discovered two new bird species on the Indonesian island of Sulawesi. The two species belong to the white-eyes family.
Sulawesi is home to rich biodiversity, including both Asian and Australian species. The main island and the smaller surrounding islands also host an exceptionally large number of endemic species.
Endemic species offer scientists the chance to study how new species emerge. White-eyes, a family of passerine birds found throughout the tropics of Africa, Asia and Australia, have diversified faster than most animals, making them an ideal model for studying speciation.
"Molecular tools have increased speciation research, but delimiting species remains problematic," scientists wrote in the new study. "We investigated the evolutionary history of Zosterops species in southeast Sulawesi using mitochondrial DNA, morphometric, song and plumage analyses, to draw species limits and assess which techniques offer best resolution."
Over the last 20 years, zoologists from Trinity College Dublin have been documenting the region's biodiversity -- tracking differences in the genomes, sizes and songs of birds on Sulawesi and the surrounding islands.
After analyzing the genome, morphology and songs of the Wakatobi white-eye, found throughout the Wakatobi archipelago, located off the Sulawesi coast, scientists decided the birds should be classified as its own species. Genomic analysis confirmed the bird split from its mainland relatives around 800,000 years ago.
Scientists identified a second new species on a single island in the archipelago. The Wangi-wangi white-eye is a much older species, having split from its relatives more than a million years ago. Today, the species' closest relative lives more 2,500 miles away.
Researchers described the two new species this week in the Zoological Journal of the Linnean Society.
"These discoveries are not just of evolutionary interest -- they will also be of real conservation relevance," lead study author Darren O'Connell, who earned his PhD at Trinity and is now working at University College Dublin, said in a news release. "By highlighting the unique species special to the Wakatobi Islands we can help safeguard the remaining habitats on the islands, which are under huge pressure. We ultimately hope to have the islands recognized as an Endemic Bird Area so that they receive more conservation support."