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Our World at Risk
Cold Dinosaurs
Dinosaurs are well known from all parts of the world, and
from many different latitudes. However, the discovery
of dinosaurs from areas that were well within the Arctic
and Antarctic during the Mesozoic is fascinating. These
so-called polar dinosaurs pose a biological enigma: how
did they cope with the hostile polar winters? Did they
migrate? Did they overwinter? And if they did stay, how
did they survive? These questions have long plagued
paleobiologists, and various theories have been put
forward to explain these findings.
Studying Dwarf Elephants
Matthew Scarborough of the Palaeobiology Research
Group in UCT’s Department of Biological Sciences
is a PhD student investigating the rather unusual
evolution of fossil dwarf elephants and mammoths on
Mediterranean islands (particularly Sicily, Malta and
Sardinia) over the last one million years. Scarborough’s
research is aimed at gaining a better understanding
of how elephants and mammoths adapted to different
kinds of island environments.
Research Projects
A recent study by a team of dinosaur palaeontologists
from UCT, Temple University (USA), and the Museum of
Nature and Science (USA) has uncovered information
recorded in the bones of duck-billed dinosaurs that
lived in the Arctic about 70 million years ago which
suggests that they did not migrate, but rather endured
the long, dark, polar night.
One of the collaborators in this study, Dr Anthony
Fiorillo, and UCT palaeobiologist Professor Anusuya
Chinsamy-Turan reasoned that perhaps clues pertaining
to how these dinosaurs lived at such high latitudes
might be recorded in the microscopic structure of
their bones. This collaboration grew to include UCT
postdoctoral researcher Dr Daniel Thomas and Temple
University’s Allison Tumarkin-Deratzian.
These researchers found that the bones of the polar
dinosaurs had an unusual texture, similar to tree rings
– the bones showed periodic changes in texture which
suggest a fast and slower rate of bone deposition,
which probably correspond to a summer and winter
bone pattern and are likely to be related to the
availability of food.
The research is particularly exciting because the data
from the bone histology independently corroborates
what researchers are seeing in the field. The results
highlight the importance of both biological and
geological evidence for interpreting the life habits of
extinct organisms.
How did they cope with the hostile
polar winters? Did they migrate? Did
they overwinter? And if they did stay,
how did they survive?
The research enables collaboration at an
international level; he has spent time in Rome,
Palermo and Basel studying the anatomy of the
feet and limbs of Sicilian dwarf elephants. For
the most part, his recent research has focused on
explaining several unusual anatomical features in
the feet of dwarf elephants, using a comparative
approach to investigate to what extent dwarf
elephant locomotion was adapted to the very
hilly environment of Sicily. During the course of
conducting fieldwork, he visited caves and a quarry
in north-western Sicily where these dwarf elephants
were found. Scarborough is attempting to date
the age of the fossils from Alcamo Quarry using
a radiometric dating technique (Uranium-Thorium
dating), and is also planning to investigate the
palaeogeography of Sicily.
A rather unexpected recent finding has been the
documentation of dwarf elephant bones which fall
outside the size ranges currently accepted for the
two dwarf elephant species which inhabited Sicily.
Research on the possible existence of a third species
of dwarf elephant on Sicily and Malta is still ongoing.
1m high dwarf elephants (Palaeoloxodon ‘falconeri‘)
from Spinagallo Cave, Sicily. With kind permission of
the Museo di Palaeontologia, Roma, Italy.