Sept. 26 (UPI) -- After decades of disagreement and debate, scientists have agreed to name Vorombe titan, an extinct Madagascan species, the "world's largest bird."
Some 12,000 years ago, Madagascar was home to several colossal, flightless bird species, dubbed elephant birds. The birds belong to the family Aepyornithidae, but disagreements over the structure of the family tree has led to confusion over which of the species deserved the title of world's largest bird.
Through the years, various studies have described the existence of 15 different species of elephant birds belonging to two different genera. The latest research -- published this week in the journal Royal Society Open Science -- suggests there are only four distinct elephant bird species. The four species belonging to three genera.
In the 19th century, scientists first claimed Aepyornis maximus was the largest known bird species. In 1894, British scientist C.W. Andrews claimed he'd found an even large species. He called the elephant bird Aepyornis titan. Critics dismissed his claims, arguing Aepyornis titan was simply an especially large A. maximus specimen.
Similar disagreements have cropped up over the last century-plus. To settle the debates, researchers at the Zoological Society of London's Institute of Zoology reexamined dozens of elephant bird fossils from museums across Europe. The team of researchers used a combination of machine learning and Bayesian clustering, a type of statistical modeling, to analyze the taxonomic data.
Their efforts showed Andrews was correct, Aepyornis titan was indeed a distinct species -- and the largest.
The shape and size of the titan bird's bones were so unique and so much larger than those of other elephant bird spices, ZSL scientists decided to rename the species Vorombe titan -- granting the bird a new genus classification.
"Elephant birds were the biggest of Madagascar's megafauna and arguably one of the most important in the island's evolutionary history -- even more so than lemurs," James Hansford, a researcher at ZSL's Institute of Zoology, said in a news release. "This is because large-bodied animals have an enormous impact on the wider ecosystem they live in via controlling vegetation through eating plants, spreading biomass and dispersing seeds through defecation. Madagascar is still suffering the effects of the extinction of these birds today."
Scientists hope their work will help ecologists better protect Madagascar's biodiversity and guard against similar extinctions moving forward.
"Without an accurate understanding of past species diversity, we can't properly understand evolution or ecology in unique island systems such as Madagascar or reconstruct exactly what's been lost since human arrival on these islands," said Samuel Turvey, professor at ZSL's Institute of Zoology. "Knowing the history of biodiversity loss is essential to determine how to conserve today's threatened species."