Pterosaurs could change the colour of their FEATHERS to attract mates or keep cool

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Prehistoric flying reptiles known as pterosaurs were able to change the colour of their feathers to attract mates or keep cool, a new study has revealed.

Pterosaurs lived side by side with dinosaurs, 230 to 66 million years ago. 

It had been known that pterosaurs had fluffy coats consisting of hair-like fibres called pycnofibres, but whether or not these structures were ‘true’ feathers had been debated.  

Now researchers from University College Cork have carried out a new study of a 115 million year old fossilised headcrest of the the pterosaur Tupandactylus imperator from north-eastern Brazil.

This species of pterosaur had a wingspan of over 16 feet – as big as a light plane – and is famous for its bizarre huge headcrest.

The team discovered that the bottom of the crest had a fuzzy rim of feathers, with short wiry hair-like feathers and fluffy branched feathers.

‘We didn’t expect to see this at all’, said lead author Dr Aude Cincotta, ofUniversity College Cork

‘For decades palaeontologists have argued about whether pterosaurs had feathers. The feathers in our specimen close off that debate for good as they are very clearly branched all the way along their length, just like birds today.’

Artist’s reconstruction of the feathered pterosaur Tupandactylus, showing the feather types along the bottom of the headcrest: dark monofilaments and lighter-coloured branched feathers

Artist’s reconstruction of the feathered pterosaur Tupandactylus, showing the feather types along the bottom of the headcrest: dark monofilaments and lighter-coloured branched feathers

The team then studied the feathers with high-powered electron microscopes and found preserved melanosomes – granules of the pigment melanin. 

Unexpectedly, the study in Nature shows the melanosomes had different shapes depending on the type of feather.

Co-lead author Professor Maria McNamara, also from Cork, said: ‘In birds today, feather colour is strongly linked to melanosome shape.

‘Since the pterosaur feather types had different melanosome shapes, these animals must have had the genetic machinery to control the colours of their feathers.

‘This feature is essential for colour patterning and shows colouration was a critical feature of even the very earliest feathers.’

Artist’s reconstruction of the feathered pterosaur Tupandactylus, showing the feather types along the bottom of the headcrest: dark monofilaments and lighter-coloured branched feathers

Artist’s reconstruction of the feathered pterosaur Tupandactylus, showing the feather types along the bottom of the headcrest: dark monofilaments and lighter-coloured branched feathers

Pterosaurs were reptiles that soared above the heads of the dinosaurs 230 to 66 million years ago. Despite flying, they are only distantly related to birds.

Varying the pigmentation of feathers would have been useful for heat insulation – and display, explained Prof McNamara.

Birds today undergo moulting – a natural process which also allows them to shed old, dull feathers and replace them with more vibrant ones.

Tupandactylus lived by a lake and was probably omnivorous – feasting on a variety of foods ranging form fish to fruit, seeds and small vertebrates.

Working with a private donor, the remarkable specimen has been now been repatriated to Brazil.

Co-lead author Dr Pascal Godefroit, of the Royal Belgian Institute of Natural Sciences, said: ‘It is so important scientifically important fossils such as this are returned to their countries of origin and safely conserved for posterity.

‘These fossils can then be made available to scientists for further study and can inspire future generations of scientists through public exhibitions that celebrate our natural heritage.’

University College Cork (UCC) Professor Maria McNamara holding tiny samples of the pterosaur feathers

University College Cork (UCC) Professor Maria McNamara holding tiny samples of the pterosaur feathers 

Prof Mike Benton, of Bristol University who was not involved in the study, said it proves once and for all pterosaurs had feathers – an idea that had been controversial.

He said: ‘The various species of Tupandactylus and their relatives had differently shaped crests – structures built from skin stretched over the bony spars – each bearing irregular, large spots of colour.

‘These crests are generally interpreted to have been for signalling between individuals. Perhaps they were used in pre-mating rituals, just as certain birds use colourful tail fans, wings and head crests to attract mates.

‘Communication was also suggested as the function of the colourfully patterned feathers on the tails, wings and heads of some dinosaurs.

‘Modern birds are renowned for the diversity and complexity of their colourful displays, and for the role of these aspects of sexual selection in bird evolution.

‘The same might be true for a wide array of extinct animals – including dinosaurs and pterosaurs.’

PTEROSAURS WERE FLYING REPTILES THAT LIVED IN THE JURASSIC AND CRETACEOUS

Neither birds nor bats, pterosaurs were reptiles who ruled the skies in the Jurassic and Cretaceous periods.

Scientists have long debated where pterosaurs fit on the evolutionary tree.

The leading theory today is that pterosaurs, dinosaurs, and crocodiles are closely related and belong to a group known as archosaurs, but this is still unconfirmed.

Neither birds nor bats, pterosaurs were reptiles who ruled the skies in the Jurassic and Cretaceous periods (artist's impression pictured)

Neither birds nor bats, pterosaurs were reptiles who ruled the skies in the Jurassic and Cretaceous periods (artist’s impression pictured)

Pterosaurs evolved into dozens of species. Some were as large as an F-16 fighter jet, and others as small as a sparrow.

They were the first animals after insects to evolve powered flight – not just leaping or gliding, but flapping their wings to generate lift and travel through the air.

Pterosaurs had hollow bones, large brains with well-developed optic lobes, and several crests on their bones to which flight muscles attached. 

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