Ending decades of doubt, 'biggest bird' dispute put to nest
Zoological Society of London (ZSL)/Zoological Society of London (ZSL) / Jaime CHIRINOS
Big bird: One species of elephant bird stood over three-metres tall and could weigh as much as a fully grown giraffe
After more than a century of conflicting evidence,
Anglo-French animosity and a H.G. Wells novella involving murder most
fowl, scientists said Wednesday they have finally solved the riddle of
the world's largest bird.For 60 million years the colossal, flightless elephant bird -- Aepyornis maximus -- stalked the savannah and rainforests of Madagascar until it was hunted to extinction around 1,000 years ago.
But a study released Wednesday by British scientists suggests that one species of elephant bird was even larger than previously thought, with a specimen weighing an estimated 860 kilogrammes (1,895 pounds) -- about the same as a fully grown giraffe.
"They would have towered over people," James Hansford, lead author at the Zoological Society of London, told AFP. "They definitely couldn't fly as they couldn't have supported anywhere near their weight."
In the study, published in the journal Royal Society Open Science, Hansford examined elephant bird bones found around the world, feeding their dimensions into a machine-learned algorithm to create a spread of expected animal sizes.
Until now, the largest-ever elephant bird was described in 1894 by the British scientist C.W. Andrews as Aepyornis titan -- a larger species of Aepyornis maximus.
But a French rival of Andrews dismissed the discovery of titan as just an outsized maximus specimen, and for decades the debate remained deadlocked.
Hansford said his research proved titan was indeed a different species. But he also found that its bones were so distinct from other elephant bird specimens that titan was in fact an entirely separate genus.
Named Vorombe titan -- Malagasy for "big bird" -- the creature would have stood at least three metres (10 feet) tall, and had an average weight of 650 kilogrammes, making it the largest bird genus yet uncovered.
"At the extreme extent we found one bone that really pushed the limits of what we now understand about bird size," said Hansford, referring to the 860-kilogramme specimen.
"And there were some that led up to that too, so it's not an outlier -- there was a range of masses that are extraordinarily large."
- Extinct, but not forgotten -
A close cousin of the now-extinct moa in New Zealand, the elephant bird belonged to the same family of flightless animals that today includes the kiwi, emu and ostrich.
Its petrified eggs still fetch large sums at auction, and it stars in Wells' 1895 work "Aepyornis Island" alongside a pugnacious mercenary named Butcher who improbably ends up living with -- and eventually killing -- one of the creatures.
Despite having one of the longest existences of any animal in Madagascar -- whose isolation from the rest of Africa led to the development of several entirely unique species -- the elephant bird died out after a new wave of human settlers arrived around a millenium ago.
"You start to see large amounts of agricultural settlements and habitat change with burning of forests... that seems to have driven all the megafauna in Madagascar, including the elephant bird, to extinction," said Hansford.
Far from being an ancient curiosity, Hansford believes the elephant bird could hold vital clues as to how to manage Madagascar's future ecosystem, despite being extinct for 1,000 years.
Elephant birds "probably played the most significant roles in maintaining and developing the landscapes that were natural to Madagascar before humans got there," he said.
"We need to understand the role of these animals within these landscapes in order to start regenerating and conserving what we have left."
US would lose out in trade war against the world: ECB
AFP/File / Fabrice COFFRINI
ECB President Mario
Draghi and World Trade Organization chief Roberto Azevedo have warned of
protectionism's rising threat to the world economy under Donald Trump's
"America First" policies
Economic activity in the United States could fall more
than two percent within a year if Washington launched a trade war on a
wide front, European Central Bank researchers suggested Wednesday.The forecast comes as officials like ECB President Mario Draghi and World Trade Organization chief Roberto Azevedo warn of protectionism's rising threat to the world economy under Donald Trump's "America First" policies.
They simulated Washington hitting all imports with 10-percent tariffs and America's trade partners responding in kind -- a far more drastic scenario than Trump has so far toyed with.
As well as the tariffs' direct effects on trade, the economists tried to capture the effect on public and financial market confidence by simulating a jump in government borrowing costs and a slump in global stock markets -- as large as 16 percent for the US.
Under that combined scenario, "real economic activity in the United States could be more than two percent lower than the baseline in the first year alone," they said.
They further predict that after three years, GDP would still be one percent below its starting level.
- 'Clearly worse off' -
"An economy imposing a tariff which prompts retaliation by other countries is clearly worse off," the economists concluded.
"Its living standards fall and jobs are lost."
In trade, while US consumers and firms might gradually switch to buying American in response to more expensive imports, the effect is at first outweighed by the drop in exports as the country's trade partners buy less.
Companies are also expected to invest less and hire fewer workers, amplifying the braking effect on the economy.
Meanwhile, China is expected to win out in the early stages of the simulated trade war.
With tariffs only affecting trade with the US, other countries could switch to buying Chinese rather than American exports, more than making up for reduced sales to the US.
More broadly, the blow to confidence from a general trade war would produce "a significant and more wide-ranging impact on output across countries," the economists found, shrinking the global economy 0.75 percent in the first year.
A near-3.0-percent contraction in overall trade would also weigh on world output.
"The scenario of a global trade war will have a dramatic effect," WTO boss Azevedo told German business leaders in Berlin Tuesday, warning that Washington was offering a "challenge to basic principles" of international exchange.
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