The loss of the pterosaur family
was a matter of been unable to survive the impact of the KT event. This is important in terms of understanding
the possibility of remnant populations anywhere. The only possible place they might have
partially endured is in South East Asia .
This also strongly suggests that
the bulk of modern bird species likely passed through that same bottle
neck. Their greater natural activity may
well have led to their swift repopulation of the globe. Recall also that we do have a small flying
reptile in Indonesia .
We have already posted on
possible sightings of such remnant populations and their nocturnal nature. We do have congruent sightings.
We do not seem to have much in
the way of smaller types, but the larger types appear to have had the capacity
to leave South East Asia .
It all really does beg the
question of why this group of creatures actually disappeared at all. The birds certainly did not. They would not have been stranded in a
refugia in which dropping biodiversity doomed them as surely happened to their
dinosaur cousins. They could escape if
they survived the initial shock.
We have already speculated that
the Chupacabra is a flying reptile modified to ingest blood. It is also nocturnal. It is also likely that the clan of pterosaurs
were also nocturnal. This makes
observation unlikely.
A whole flock of fish eating
pterosaurs could live in a rock bound high
point outside the possibility of discovery and fish
only at night. We would never know and their
ability to avoid us would be excellent. I do not think this is particularly true but
as I have long since understood, such a possibility must never be discounted.
The rise and rise of the flying reptiles
by Staff Writers
Extremes in pterosaur morphology. The giant and probably flightless
Quetzalcoatlus from the Late Cretaceous of Texas was as tall as a giraffe. The small
insectivorous Anurognathus from the Late Jurassic of Germany is seen flying above the
artist's head. Drawings by Mark Witton.
A new study by Katy Prentice, done as part of her undergraduate degree
(MSci in Palaeontology and Evolution) at the University of Bristol, shows that
the pterosaurs evolved in a most unusual way, becoming more and more
specialised through their 160 million years on Earth. The work is published in
the Journal of Systematic Palaeontology.
'Usually, when a new group of animals or plants evolves, they quickly
try out all the options. When we did this study, we thought pterosaurs would be
the same,' said Katy.
'Pterosaurs were the first flying animals - they appeared on Earth 50
million years before Archaeopteryx, the first bird - and they were good at what
they did. But the amazing thing is that they didn't really begin to evolve
until after the birds had appeared.'
Katy's study was done in conjunction with her supervisors, Dr Marcello
Ruta and Professor Michael Benton. They looked at 50 different pterosaurs that
ranged in size from a blackbird to the largest of all, Quetzalcoatlus, with
a wingspan of 12 metres, four times the size of the largest flying bird today,
the albatross.
They tracked how all the pterosaur groups came and went through their
history and recorded in detail their body shapes and adaptations.
The new work shows that pterosaurs remained conservative for 70 million
years, and then started to experiment with all kinds of new modes of life.
After birds emerged and became successful, the pterosaurs were not pushed to
extinction, as had been suggested. It seems they responded to the new flyers by
becoming larger and trying out new lifestyles.
Many of the new lifestyle adaptations were seen in the pterosaurs
skulls, as they adapted to feed on different food sources; some were
seed-eaters, many ate fish, and later ones even lost their teeth. The rest of
the body also showed a surprising amount of variation between different groups,
when considering that the body forms have to retain many features to allow
flight.
'Pterosaurs were at the height of their success about 125 million years
ago, just as the birds became really diverse too,' said Dr Marcello Ruta. 'Our
new numerical studies of all their physical features show they became three
times as diverse in adaptations in the Early Cretaceous than they had been in
the Jurassic, before Archaeopteryx and the birds appeared.'
Pterosaurs dwindled and disappeared 65 million years during the mass
extinction that killed the dinosaurs. In their day they had been a fair match
for the birds, and the two groups divided up aerial ecospace between them, so
avoiding conflict.
'We're delighted to see a student mastering some tough mathematical
techniques, and coming up with such a clear-cut result,' said Professor Michael
Benton. 'Palaeontologists have often speculated about the coming and going of
different groups of animals through time, but the new study provides a set of
objective measurements of the relative success and breadth of adaptation of
pterosaurs through their long time on the Earth.'
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