New identity for the world's largest bird

Illustration of the giant elephant bird by an artist. c) Jaime Chirinos

After decades of contradictory evidence and numerous publications, scientists at the Zoological Institute of ZSL, the international conservation organization, have finally ended the debate over the world's largest bird.

Published today (September 26, 2018) in the Royal Society Open Science – the titan Vorombe (which means "big bird" in Malagasy and Greek) took the title with weights reaching 800 kg and three meters in height. in these Malagasy creatures.

Until now, it had been suggested that up to two different species of elephants had been identified under two different genera, but research conducted by ZSL scientists demonstrates new rigorous and quantitative evidence, which shows that this is not the case. Armed with a tape measure and a pair of compasses, Dr. Hansford has analyzed hundreds of elephant bones from museums around the world to discover the world's largest bird, while revealing that their taxonomy is extends over three genera and at least four distinct species. thus, constituting the first taxonomic reassessment of the family for more than 80 years.

Illustration of the giant elephant bird by an artist. c) Heidi Ma

Elephant birds (belonging to the family Aepyornithidae) are an extinct group of colossal birds, unable to fly, which roamed Madagascar at the end of the Quaternary, with two genera (Aepyornis and Mullerornis) previously recognized by scientists. The first species to be described, Aepyornis maximus, has often been considered the largest bird in the world. In 1894, British scientist C.W. Andrews described an even larger species, Aepyornis titan, which was generally considered to be an exceptionally large specimen of A. Maximus. However, ZSL's research reveals that Andrew's titan bird was indeed a distinct species. The shape and size of his bones are so different from those of all other elephants that he has now been given the new name of genus Vorombe by ZSL.

The lead author of the ZSL Zoology Institute, James Hansford, said: "Elephant birds were the largest of Madagascar's megafauna and probably one of the most important in the history of Madagascar. evolution of the island – even more than lemurs. Indeed, large animals have a huge impact on the ecosystem in which they live by controlling vegetation by eating plants, spreading biomass and dispersing seeds through defecation. Madagascar is still suffering the effects of extinction of these birds today. "

Professor Samuel Turvey of the Zoology Institute of ZSL said: "Without an accurate understanding of the diversity of species of the past, we can not understand the evolution or ecology in island systems unique as Madagascar or islands. Knowing the history of biodiversity loss is essential in determining how to conserve today's threatened species.

Vorombe Titan Os. (c) ZSL

By analyzing this data in a new combination of machine learning and Bayesian clustering, Dr. Hansford applied modern techniques to solve a 150-year-old taxonomic node, which will constitute the modern understanding of these mega-avian enigmatics. The revelation that the largest of these birds has been forgotten by history is only part of their remarkable history.

Publication: James P. Hansford, Samuel T. Turvey, "Unexpected diversity among extinct elephants (Aves: Aepyornithidae) and a new identity for the world's largest bird", Royal Society Open Science, 2018; DOI: 10.1098 / rsos.181295