A research study published in June 2022 in the Communications Biology journal found that the Hummingbird species, collectively, is more colourful than any other type of bird.
One way to measure colourfulness is to consider the theoretical total number of colours a bird can detect, and then estimate how many of these colours are produced on the feathers of the bird. Most birds can see more colours than humans can see because birds have extra receptors in their eyes to detect light in the ultraviolet (UV) spectrum of colour. Using this method, a 2011 study published in the Behavioral Ecology journal by researchers from the University of Cambridge in the United Kingdom and Yale University in America, found that birds typically produce on their feathers only about 30% of the colours they see.
In this new 2022 study, Gabriela Venable at the Duke University in North Carolina, America, and her researchers, looked at 114 species of Hummingbirds. It is the first time that a group of related birds have been studied in relation to colourfulness.
Hummingbirds are small, nectar-supping birds in the Trochilidae family and are found in the Americas.
The researchers found that the collective group of Hummingbird species can produce on their feathers 34% of the colours that they see. They can also produce the colours deep purple and blue that are rare in other birds.
The researchers found that Hummingbirds have pigment-producing organelles (colour dyes) in their feathers that are layered in such a way that they use light to produce vibrant colours. Researcher Gabriela Venable said, ‘This type of structural colouration is fairly unique to Hummingbirds because of the shape of their organelles which are disc-shaped and hollow, allowing for the creation of saturated colours.’
They found that the most colourful parts of the Hummingbird were the throat and top of the head. ‘Hummingbirds use these colourful patches to show off or when they want to say this is my territory and puff themselves out,’ Gabriela Venable said.
However, the researchers don’t fully know why the Hummingbird would need to be more colourful than any other type of bird.
Journal reference: Communications Biology, DOI: 10.1038/s42003-022-03518-2
Photographer: Glenn Bartley
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