High-speed flight recordings of lovebirds making quick in flight turns reveal how these birds improve sight and shorten blur by rotating their head at speeds of up to 2,700 degrees per second, as fast as insects, enabled by fast neck muscles.
The rosy-faced lovebird (Agapornis roseicollis). Image credit: David González Romero.
Lovebirds are any of the nine species of the parrot genus Agapornis (family Psittaculidae).
One species, the grey-headed lovebird (Agapornis canus), is native to Madagascar, and eight species are native to the African continent.
These birds were called lovebirds because of their monogamous pair bonding.
They are small, compact parrots around 5 – 6 inches (12.5 – 15 cm) in length 40 – 60 grams in weight.
According to a new study published in the journal PLoS ONE, during flight, turning lovebirds rotate their head at up to 2,700 degrees per second, faster than any other vertebrate recorded to date.
The authors of the study – Dr Daniel Kress and his colleagues from Stanford University – discovered this super-fast behavior by filming the maneuver at 2,000 frames per second during a goal-directed task.
For flight recordings, they trained five rosy-faced lovebirds (Agapornis roseicollis) to turn on a dime in a custom-built flight arena.
“The first step was to train the birds to fly between two perches. In the second step, one perch was removed and birds were trained to fly away, turn and return to the remaining perch. During the third step, the width of the perch was decreased to about 21 cm, after which the birds were ready for the experiment,” the scientists wrote in the paper.
Analysis of high-speed recordings revealed that rapidly turning lovebirds execute extremely fast head turns during turning maneuvers.
The birds time these head turns precisely when their wings are covering their eyes, this minimizes the time of obscured sight.
Consequently, they shorten phases of blurry and obscured sight into a fraction of the actual turning time, resulting in stable and clear vision during the rest of the maneuver.
“The lovebird’s rapid head turn probably enables them to make split second decisions during rapid turns,” the scientists said.
They also hope that the accuracy and speed of these visually guided flight-maneuvers may inspire camera rotation design in drone to improve imaging.
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Kress D et al. 2015. How Lovebirds Maneuver Rapidly Using Super-Fast Head Saccades and Image Feature Stabilization. PLoS ONE 10 (6): e0129287; doi: 10.1371/journal.pone.0129287
