Imagine an ostrich-like bird that weighed about the same as an adult giraffe. Sounds like the stuff of fantasy? Not so.
For about 150 years now, there has been debate over what the largest bird ever to roam the Earth was - the debate has been intense, largely due to highly competitive scientists claiming to have discovered a new species of 'Elephant Bird'.
Elephant birds were several species of colossal, flightless birds native to Madagascar, and they co-existed with humans until they were hunted to extinction about a thousand years ago.
Now, it looks as if this long-running debate has now come to an end.
James Hansford is a palaeontologist at the Zoological Society of London, and lead author of a new study which identifies the species Vorombe Titan – at around 800kg - as the largest bird that has ever existed. James joined Mooney Goes Wild from London to explain more - listen back above.

For more information on James and his work, click here, and to read his paper, as published in Royal Society Open Science, click here.
Elsewhere on last night's episode...
Did you know that birds have personalities? New research into bird-bonding suggests that they most certainly do - Professor John Quinn tells us why.
Eanna ni Lamhna has news of the latest NPWS report into raptor deaths. Terry Flanagan reports on how a specially-designed garden is helping sufferers to continue to live well with dementia.
Listen back to last night's episode in the video above.
- Words by Sinead Renshaw
Tune into Mooney Goes Wild every Monday, 10pm-11pm on RTÉ Radio 1.
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