Argentavismagnificens, the largest bird to have ever inhabited Earth, lived six millionyears ago in the southern part of South America that roughly corresponds tomodern-day Argentina. The bird, which is known only through fossil remains,weighed up to 68 kilograms. There is some debate about whether this bird wasable to fly or whether it had lost its ability to fly at some point during itsevolution.
First, there is theproblem of lifting off into the air.
Second, even if thebird had managed to lift off, it does not appear to have had enough musclestrength to make continuous flight possible. As
Third, according tothe theory of evolution, animals only have abilities that give them anadvantage in their struggle to survive.
First, instead oftaking off from a standing position, the birds could have used their runningstyle.
Second, there is noreason why the bird would have had to keep flapping its wings in order to stayin the air. It could have stayed in the air by catching so-called thermal, warmcurrent air that rises up into the atmosphere.
Third, the abilityto fly would have been very useful for this bird. Why? Because it was probablya scavenger.