Triceratops and Oviraptor, we can see the
inner bony part of a beak that, in life,
would likely have been covered with an
outer keratinous layer as in birds today.
Keratin is the same tough protein that
feathers, hair, fur and fingernails are made
of. Did dinosaurs have lips? This is
something we still don’t know, and is an
area of current debate.
FLUFFY THEROPOD
Carnivorous theropods, in contrast to the
herbivores, were frequently covered in
feathers. The incredible fossils of nearly
50 species – mostly from China’s north-
eastern province of Liaoning – show a
range of feathery coverings, from downy,
insulating ‘dino-fuzz’ to flashy display and
flight feathers. Some of these animals are
so exquisitely preserved that we can see
the shape and arrangement of feathers
right across their bodies.
Though most of these feathered
dinosaurs have been found in China, the
spread of species across the family tree
suggests that most theropods in other
parts of the world were feathered too- we just have a fantastic window into
the past with Liaoning because of the
type of preservation found in its volcanic
deposits.
Sometimes we have other evidence of
feathers, such as marks on the forearm
bones of Velociraptor which correlate to
the ‘quill knobs’ where the ligaments of
flight feathers attach on pigeons today. It’s
this feature in Velociraptor fossils from
Mongolia that led experts to assume all
dromaeosaurs had small ‘wings’ on their
forearms – a feature now confirmed by
the Chinese fossil of another new
dromaeosaur called Zhenyuanlong,
described in 2015 by scientists including
Dr Stephen Brusatte at the University of
Edinburgh. Quill knobs were also found
in the Dakotaraptor fossil, and the
scientists behind this discovery, led by
Robert DePalma at the Palm Beach
Museum of Natural History in Florida,
estimated it to have had a wingspan of
around a metre.
Artists also play an essential role in
bringing dinosaurs to life, and often have
expert anatomical and palaeontological
knowledge to build on the scientific
evidence with informed guesswork.
Without these palaeoillustrators, such as
Emily Willoughby who created the
lovely feathery image of Dakotaraptor,
the appearance of these animals would
live only inside the minds of the scientists
who discovered them.
In the last five years, the colours of
dinosaur feathers have come into focus,
but we may soon have a good idea of
dinosaur skin colours too. We already
know from the patterns of scales on some
‘mummified’ fossils that Edmontosaurus
was probably adorned with stripy patterns,
even if we’re not sure what colour they
were, and a number of studies have started
to use electron microscopes to look at the
structural patterns of tiny packages of
pigment in the skin. Last year, an
international team of scientists used this
technique to show that a prehistoric
marine reptile called a mosasaur had a dark
back and a pale-coloured belly, while
another marine reptile – a dolphin-shaped
ichthyosaur – had universally dark
pigmentation. It won’t be long before
similar methods are used to determine the
colours of dinosaurs too.
Reconstructing animals from fossils is
partly guesswork, but it’s informed
guesswork, building on the knowledge
built up over the centuries by pioneering
palaeontologists. Today, we have a better
idea of the appearance of dinosaurs than
ever before. ßJOHN PICKRELL IS A SCIENCE JOURNALIST
AND AUTHOR OF FLYING DINOSAURS: HOW FEAR-
SOME REPTILES BECAME BIRDSCOMPARATIVE ANATOMY
The study of similarities and
differences in the physical features of
various species. This allows experts
to make informed guesses about the
appearance of extinct species based on
living animals.
MELANOSOMES
These tiny granules of pigment are
responsible for the colouring of hair and
feathers in animals and birds. Preserved
melanosomes in a Sinosauropteryx fossil
revealed this dinosaur’s true colours.
PALAEONTOLOGY
The study of prehistoric life, based
on the fossils of animals, plants and
other organisms, as well as the ages and
details of the layers of rock they were
found in.
THEROPOD
This large group of bipedal and
mostly carnivorous dinosaurs includes T.
rex, Allosaurus and Sinosauropteryx. The
first birds evolved from theropods around
150 million years ago.
Zhenyuanlong was discovered in the Liaoning region of China. It lived in the Cretaceous period, around 125 million
years ago. The fossilised remains suggest that this dinosaur was covered in feathers4
3
2
1
NEED TO KNOW
A quick glossary of key terms used
in dinosaur appearance