How birds learnt to fly decoded

Birds have an innate ability to manoeuvre in midair, a talent that could have helped their ancestors learn to fly rather than fall from a perch, scientists have found.
The study by the University of California, Berkeley, looked at how baby birds, in this case chukar partridges, pheasant-like game birds from Eurasia, react when they fall upside down.
The researchers, Dennis Evangelista, now a postdoctoral researcher at the University of North Carolina, Chapel Hill, and Robert Dudley, UC Berkeley professor of integrative biology, found that even ungainly, day-old baby birds successfully use their flapping wings to right themselves when they fall from a nest, a skill that improves with age until they become coordinated and graceful flyers.

"From day one, post-hatching, 25 per cent of these birds can basically roll in midair and land on their feet when you drop them," said Dudley.
"This suggests that even rudimentary wings can serve a very useful aerodynamic purpose," Dudley said.
The nestlings right themselves by pumping their wings asymmetrically to flip or roll.

By nine days after hatching, 100 per cent of the birds in the study had developed coordinated or symmetric flapping, plus body pitch control to right themselves.
"These abilities develop very quickly after hatching, and occur before other previously described uses of the wings, such as for weight support during wing-assisted incline running," said Evangelista.

"The results highlight the importance of manoeuvring and control in development and evolution of flight in birds," said Evangelista.
Dudley has argued for a decade that midair manoeuvrability preceded the development of flapping flight and allowed the ancestors of today's birds to effectively use their forelimbs as rudimentary wings.
The new study shows that aerial righting using uncoordinated, asymmetric wing flapping is a very early development.
Righting behaviour probably evolved because "nobody wants to be upside down, and it's particularly dangerous if you're falling in midair," Dudley said.
"But once animals without wings have this innate aerial righting behaviour, when wings came along it became easier, quicker and more efficient," said Dudley.

The research was published in the journal Biology Letters.