Environment in which dinosaurs lived
Was the climate in the Age of Dinosaurs similar to that of today?
No. The Earth's climate has varied greatly throughout time. At some stages in the Earth's history, the climate was very cold, resulting in Ice Ages. At other times the climate was quite warm. For much of the Mesozoic Era (the Age of Dinosaurs), parts of Australia would have experienced a colder and wetter climate than we have at present, due largely to the more southern location of the Australian continent.
How does this climate change affect the Earth?
For many millions of years, the primary drivers of
climate change have been the positioning of the continents,
mountain and ocean building as a result of continental
drift, and continent building resulting from volcanic
activity. As the climate changed over time, so too
did the environment and the types of animals and plants
it could support.
What climate did Australia's dinosaurs live in during the Cretaceous Period?
When the Cretaceous
Period began, about 140 million years ago,
Australia had a cool, temperate climate that was
very gradually warming as the continent began
to move away from the South Pole. The landscape
was dominated by conifers, pines and ferns as
well as some of the first flowering plants. Australia's
proximity to the South Pole would have resulted
in lower levels of light and a landscape similar
to that of a woodland environment.
Why do scientists think this big sea existed?
Layers of rock from the Cretaceous Period in the Great Artesian Basin contain many fossils of marine (sea) dwelling animals, proving the area was once covered by the sea. These animals included some very large reptiles such as the plesiosaurs, ichthyosaurs, and crocodiles. You may like to investigate these animal groups.
Were any of these marine animals dinosaurs?
No. The dinosaurs were all terrestrial (land-dwelling) animals.
Was the climate consistent throughout Australia at that time?
No. Australia's climate was cool to temperate during the Cretaceous and, although the climate gradually warmed throughout the period, the northern parts of Australia may have been somewhat warmer than the southern parts, which were close to the South Pole. Australia was still joined to Antarctica during the Cretaceous, but even so, the conditions would have been more temperate than modern Antarctica. Fossils show that it was mild enough for trees to grow.
Did the same dinosaur species occur all over Australia?
Fossils indicate that northern dinosaurs, such as those found in what is now central Queensland, may have been different from the southern (or 'polar') dinosaurs whose fossils have been found in Victoria. The polar dinosaurs seem to have been smaller and adapted to living in a colder climate.
What did the dinosaurs eat?
Many dinosaurs ate plant stems and leaves. Plant-eating animals are known as herbivores. Other dinosaurs were meat-eaters and these are called carnivores. Still others would have eaten insects (insectivores), and some may have eaten a mixture of plants and animals (omnivores).
How can scientists tell whether a dinosaur was a herbivore or a carnivore?
Scientists can tell a lot from studying fossils.
All living things have special features to help
them in the way that they live. Some examples
would be the ability to run fast for a hunting
animal, tough skin and spines for self defence,
sharp teeth for a meat-eating animal, stripes
for camouflage, and so on.