50 million years B.C until 2.6 million years B.C
50 to 10 million years B.C
Shifting tectonic plates. 50 to 10 million years B.C, the tectonic plates started to move which meant that there were earthquakes and volcanoes. Volcanoes were in central and western Victoria. Mountain ranges were created. This caused the climate to change. Currents were created in the sea. Bass Strait was drier. It was a flood plain with lots of plants and animals. Minerals got washed into the sea and, as a result, limestone was made. When limestone is made it takes carbon dioxide out of the air. Lots of plants didn’t like this and began to die but the grasses didn’t mind. Around 16 million years ago, the drier climate helped the evolution of harder leafed plants like eucalypts, wattles and banksias. 1 |
8 million years B.C
Grass - the terminator! Grasses evolved with bundles to suck in more CO2. This is because, in the ocean, limestone was formed. Limestone uses a lot of CO2 so there wasn’t much to go around. Grasses burn easily and don’t die. They use themselves as fuel to kill the trees and then they take the spot. 8 million years ago, the climate was drier than ever. And the smallest lightning bolt would set grass fires everywhere, killing the forests. Grass burns into a gas which burns really hot a metre above the grass – killing shrubs and trees. The growing bud of grass is protected underground by fibre insulation, only to come out when the rain falls. So now the grasses dominate and have taken over the world! |
6 million years B.C Grass Everywhere!!! 6 million years B.C there was grass everywhere. Grass burns really easily. But it doesn’t die. Trees and shrubs would get burnt to death by fires. Then the grass takes over and grows all over the place. All the grasses attracted herbivores because of the food. There were lots of herds of animals like giant kangaroos, diprotodons and giant emus. Now there are new species of herbivores. And when the trees burnt down there was no food for browsers and they became extinct. |
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5 million years B.C
Marsupials Diversified.
5 million years B.C, because there was so much grass, huge herds of grazing animals like the procoptodon goliah and the protemnodon lived in Australia. There was lots of manure which is full of silica from the grass. The manure got washed into the sea and diatoms used it. Diatoms fed the world a quarter of its oxygen. Fish fed on diatoms, and bigger fish fed on them. This meant they had the chance to have new species because of all the food to eat. While this is happening Gondwana is breaking up and leaving marsupials - herbivores and scavengers - isolated so they have the chance to diversify.
Marsupials Diversified.
5 million years B.C, because there was so much grass, huge herds of grazing animals like the procoptodon goliah and the protemnodon lived in Australia. There was lots of manure which is full of silica from the grass. The manure got washed into the sea and diatoms used it. Diatoms fed the world a quarter of its oxygen. Fish fed on diatoms, and bigger fish fed on them. This meant they had the chance to have new species because of all the food to eat. While this is happening Gondwana is breaking up and leaving marsupials - herbivores and scavengers - isolated so they have the chance to diversify.
2.6 million years B.C
Quaternary period - megafauna and a changing landscape. 2.6 million years B.C was the Quaternary period. At this time the world looks like it does today. Lower sea levels made land bridges for animals to cross to different continents meaning they could evolve differently. Large animals known as Megafauna lived all over the globe. Diprotodon, a kind of giant wombat, roamed Australia and so did flightless birds. The bedrock of Victoria was in its place except the landscape was always changing. Volcanoes got active again. Everything was drier. Rainforests started to shrink, so animals had to evolve to live in these conditions. Hard leaved plants such as eucalypts, spinifex, banksias and wattles were food for animals that came from bug to marsupial size. Megafauna lived alongside emus and kangaroos. |
300,000 B.C Volcanoes Erupting in Bullarto 300,000 years B.C lots of volcanoes were erupting near Bullarto. Poisonous gas, ash and lava were exploding from volcanoes and destroying the landscape and killing animals. The volcanoes emitted mafic lava which was slow moving and full of silica. Because it was slow moving it created a mountain shaped volcano by building up solidified rock which turned into soil as time went on. This sort of volcano was known as the composite volcano. The slow moving lava created magma chambers inside the volcanoes which filled up with magma. Lots of pressure built up in the magma chambers, finally causing the volcano to explode. Because of volcanoes, in Bullarto, mineral water can be easily pumped out of the ground. Where the magma flowed under the ground, it shaped out tunnels and water passages for water to flow through. The water was filled with minerals from the mafic lava and the soil. The lava flowed into Bullarto from the Mossop Hill area. The flow stopped just in Bullarto and 300,000 years later the lava has turned into rich soil, perfect for growing crops and farming. The climate is colder and wetter than the surrounding areas due to the land being higher. Today you can tell where the lava stopped because farmers don’t usually clear that land. So forest is still growing. |