Assignment task:
In your groups of four, collect a globe, paper cut-outs of continents and 'blu-tack'. Place the continents of Antarctica, Australia, India, Africa and South America into the Gondwanan super continent on the bench. Note how neatly the coastlines of the continents fit together.
The arrows on the continents indicate "North" and the numbers at the top and next to the arrows, e.g. 160 mya, refer to the number of million years before the present. You are given three times before the present, i.e. 160, 90 and 45 million years ago. The numbers below each "age" refer to the latitude and longitude coordinates for the tip of the arrow. When positioning the continents for each "age", ensure that the corresponding arrows point north.
For the oldest time (160 mya), using blu-tack on the back of the cut-out, place the tip of the arrow on the Antarctica cut-out at latitude 45°S and longitude 45°E on the world globe, ensuring that the arrow points north. Similarly, now place the remaining continents at the designated coordinates around Antarctica. This is the approximate position of Gondwana 160 million years ago (mya).
a. Assuming that, for any given latitude, the climatic and solar conditions were similar to the planet today, what would the conditions have been like in Australia during that time (160 mya)?
b. By 90 million years ago, Antarctica had moved to its present position. Place the cut-out of Antarctica in that position. As before, place Australia and the other continents in their positions. What has happened to Gondwana? What climate would Australia have experienced during that time? What daylight hours would Australia be subjected to in the summer and winter?
c. Now, put South America aside, and move Australia, India and Africa to their positions for 45 million years ago. Until this time, Australia was connected to Antarctica by a land bridge via Tasmania. What implications did the separation of the two continents have to the biota of Australia? How would the climate change in Australia as it moved further north?