Gondwana broke up due to the movement of the tectonic plates that make up the Earth’s crust. The breakup of Gondwana occurred in stages. Some 180 million years ago, in the Jurassic Period, the western half of Gondwana (Africa and South America) separated from the eastern half (Madagascar, India, Australia, and Antarctica)¹. The final stages of break-up, involving the separation of Antarctica from South America and Australia, occurred during the Paleogene.

(1) Gondwana | Ancient Landmass, Plate Tectonics & Climate. https://www.britannica.com/place/Gondwana-supercontinent.
(2) Gondwana – Wikipedia. https://en.wikipedia.org/wiki/Gondwana.
(3) What is Gondwana? | Live Science. https://www.livescience.com/37285-gondwana.html.