Hello and welcome to my latest publication, a celebration of
the incredible pterosaurs which ruled the skies during the Mesozoic era. From
the tiny to the enormous the diversity of these reptiles is truly staggering as
was their success. The fact they filled so many niches is testament to their
adaptability and resilience. It is no exaggeration to say that the skies of the
Mesozoic would have made a truly astounding sight. I hope you enjoy this
piece and as always feel free to give feedback.
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The emergence of pterosaurs.
From the moment reptiles appeared on earth there has always been
the potential for species to attempt to utilise the possibility of flight. It
was not however until the late Triassic period where true flight in reptiles
appeared in the incredibly diverse form of pterosaurs. Pterosaurs are divided
into two groups– rhamphorhynchoid pterosaurs and pterodactyloid pterosaurs.
Characteristics of – rhamphorhynchoid pterosaurs include a short wrist bone
which resulted in the weight of the wing predominantly based on the elongated
fourth finger. The bones of the finger itself were as thick as the arm. Rhamphorhynchoid
wings were typically longer and thinner than those of pterodactyloids. Rhamphorhynchoids
also possessed a stiff rod of vertebrae which was characterised by a diamond
shaped fin at its end. The purpose would have been to help with steering during
flight. This is a trait not found on pterodactyloids.
Pterodactyloids wrist bones were often as long as those of their
humorous. Consequently the fingers were found further along the leading edge of
the wing. In both wings an extra bone at the base of the wing it is theorised,
would have supported a membrane which stretching in front of the arm bones and positioned
between the wrist and base of the neck. The main advantage of this would have been
to manipulate air flow over the wing, providing maneuverability.
The earliest known
pterosaur –Preondactylus.
Preondactylus is the earliest known pterosaur. The species
was discovered by Nando Buffarini during the year of 1982 in the Preone valley
situated in the Italian Alps. The tail remains share the same trait as all
other rhamphorhynchoids. The vertebrae is made up of tendons which have over
time solidified into one. This would have been utilised for balancing and
steering.
Early diversity.
Peteinosaurus.
This diminutive pterosaur is thought to provide one of the
earliest examples of diversity in pterosaurs. It is considered likely the majority
of peteinosaurus diet was made up of insects rather than the predominantly fish
based diet many other pterosaurs favoured. Despite its size, it has been
suggested this species could be the ancestor of dimorphodon.
Pterosaurs of the Jurassic.
Dimorphodon.
Having recently made an appearance in Jurassic World, dimorphodon may well now be one of the most notorious
pterosaurs discovered. The first specimen of this species was discovered in the
cliffs of Lyme Regis by Mary Anning in 1828. The only other confirmed remains
of dimorphodon have also come from the Dorset Coast. Present day birds which possess
the same deep faced trait as ptersoaurs such as dimorphodon could provide
living examples of how these reptiles may have used colouration for signalling
purposes. The strong claws on the feet and hands are thought to be an adaption
for a life living on cliffs.
An end to the warm blooded debate.
The argument over where pterosaurs were warm blooded as
strongly suspected due to their lifestyle came to an end with the discovery of
sordes. So well preserved were the remains a fur like covering was clearly
apparent, a tell-tale sign of a warm blooded animal. This trait would not only
have helped with body temperature regulation, the fur would have helped to
minimise the noise of flying a useful advantage for an aerial predator.
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Aerial agility.
Rhamphorhynchoids were predominantly fish eaters, batrachongnathus
however was adapted to an altogether different lifestyle. With blunt teeth, broad
scoop like jaws and a diminutive body perfect for aerial hunting batrachongnathus
was perfectly designed for hunting down insects over lake surfaces. Experts
have likened their hunting technique to that those of modern day swallows.
The Cretaceous.
The first pterosaur to be found in South America came in the
unusual form of pterodaustro. A filter feeder, its long, thin jaws would have
sweeped upwards in a bow shape. The lower jaws were filled with up to as many
as five hundred bristles. The upper jaws possessed blunt teeth were perfect for
moving the prey towards the mouth. It has been speculated the fur of
pterodaustro was pink as a result of the pigmentation caused by feeding on
crustaceans, flamingos provide a modern day example of this.
Mysteries unsolved.
Tapejara has caused experts plenty of headaches. The short
mouth opens up two possibilities as far as its feeding preferences are
concerned. Tapejara may have been a fruit eater and as a consequence would have
played an important role in the ecosystem with seed dispersal, or on the other
hand its diet might have been made up of carrion and fish. The unusual crest
has also been a subject of debate. The immediate assumption is that the purpose
of such an ornament was for display however the crest may have been employed to
aid with aerodynamics. Tupuxuara comes from the same area as tapejara – North
Eastern Brazil and both existed during the early Cretaceous. The similarities
continue anatomically as well as tupuxuara also possessed a crest. This
possessed plentiful blood vessels inside which indicated an ability to change
colour in accordance to activity and mood. Despite this further research has
revealed that this bizarre pterosaur was not part of the same family as
tapejara as previously thought, and more closely related to one of the giants
of the skies, quetzalcoatlus.
The sheer size of quetzalcoatlus is almost impossible to
comprehend, the fact an animal of such a size ever took to the air is nothing
short of mind blowing. The wingspan alone would have been the length of a bus
and when on four limbs would almost have been able to make eye contact with a
giraffe. The weight of this goliath is a subject of debate and estimates have
ranged significantly from 250 kg to 70 kg still the weight of an average sized
human. The size of the animal initially raised doubts if flight were even
possible. Recent research has found the arm bones were so strong that, even at
the peak of the weight estimates they would still have been capable of allowing
quetzalcoatlus to get airborne. From a standing position on all fours, this
giant was able to generate enough explosive power to take off.
These animals were truly incredible. They ruled the skies
for millions of years and would have installed fear in the animals they hunted.
Their diversity was truly remarkable and we are lucky we have the clues they
have left behind to try and understand how they lived their extraordinary
lives.
I hope you have enjoyed this publication and thank you for
reading all the best, George.
Twitter - ReallyWildWykes
Email- grwykes@gmail.com
References
The
Illustrated Directory of Dinosaurs and Other Prehistoric Creatures.
The Complete Illustrated Encyclopedia of Dinosaurs & Prehistoric Creatures.
Dinosaurs The Grand Tour.
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