History

The World’s Largest Ever Bird Was as Tall As a Bungalow

The giant elephant bird weighed more than a grizzly bear, British scientists say.Thursday, October 11

By Oli Reed
An artist's impression of the colossal elephant bird.

The debate over the identity of the world’s largest ever living bird appears to have been put to rest, with the title being claimed by a giant elephant bird that roamed Madagascar more than 1,000 years ago, reaching up to 800kg in weight and standing three metres tall.

Armed with a tape measure and a pair of callipers, scientists at the Zoological Society of London recently analysed hundreds of bird bones from museums around the world. The results of their research revealed that the flightless Vorombe titan (which translates as ‘big bird’ in Madagascan and Greek) is the largest bird to have ever walked the Earth, taking the title from its relative Aepyornis maximus.

The shape and size of its bones are so different from other members of the elephant bird family that ZSL scientists have named the Vorombe titan as a new genus, and believe that due to its size it may have had no natural predators.

Huge and feathered, the 'Vorombe titan' or elephant bird, as imagined by an artist.

4-metre wingspan

“At full size, it is hard to conceive what animals could have predated such an enormous bird,” said Dr James Hansford, lead author at ZSL’s Institute of Zoology. “However, there were giant crowned eagles with 4-metre wingspans, similar to the specialised predators of the giant moa of New Zealand. In addition, there were larger species of Madagascar's largest ground-based predator, the Cryptoprocta spelea, which could have predated juvenile Vorombe titans.”

The last elephant birds are believed to have died out around 1,000 years ago, and although paleontologists don’t know the precise reason for the extinction, it is believed to have been at the hands of humans. Dr Hansford continues, “All Madagascar's endemic megafauna – animals over 40kg – became extinct at around 1,000 years ago in what is known as the ‘megafaunal extinction window’. This period tallies with extensive expansion of human settlements and habitat transformations through slash and burn of natural flora to create agricultural pasture. Although some natural climate change may have compounded this impact, humans were most likely the primary driver of extinction.”

There is still much to learn about how the Vorombe titan lived, and indeed about the lives of the elephant bird family in general. Dr Hansford intends to conduct future research into its diet and habitat, and hopes to gain a more definitive understanding of important biomechanical characteristics such as how fast they were able to move across the ground. What scientists do know, though, is that their extinction left a hole in the island’s ecosystem that still remains to be filled.

The bones of an elephant bird, 'Vorombe titan'.

Elephant birds vital for evolution

“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,” says Dr Hansford. “This is because large-bodied animals have an enormous impact on the wider ecosystem they live in. They control vegetation through eating plants, spreading biomass and dispersing seeds through defecation. Madagascar is still suffering the effects of the extinction of these birds today.”

Although the elephant bird may not have been seen in Madagascar for 1,000 years, it does share characteristics with a number of living species. Those modern relatives may not stand more than half the height of a giraffe or produce eggs large enough to feed an entire human family, as the Vorombe titan did, but they do share similar characteristics.

“Elephant birds, including Vorombe titan, are ratites,” says Dr Hansford. “The living ratites include ostrich, rhea, emu, cassowary and the closest living relative of elephant birds, New Zealand's kiwi.”

Discoveries such as this, of course, are still just further pieces that have been added to a giant and complex evolutionary puzzle that may never fully be understand.

“There are still many gaps in the non-avian fossil bird record,” says Sandra Chapman, curator of fossil reptiles and birds at London’s Natural History Museum. “This discovery is important for our understanding of the evolution and diversity of the gigantic terrestrial birds that live today, such as the ostrich, emu, rhea and cassowary.”

The length of the bones give a clue to the enormous size of the elephant bird, 'Vorombe titan'.

Is there a bigger bird waiting to be discovered?

But does this, at least, finish the debate over the largest ever species of bird? Or could future research bring further surprises and revelations?

“Never say never,” says Chapman. “The fossil record of non-avian flightless birds has many gaps, so perhaps another gigantic terrestrial bird will be discovered.”