In 1912, Alfred Lothar Wegener, a German climatologist, geologist, geophysicist, meteorologist & polar researcher, proposed what is today accepted as the 'continental drift theory'. He observed that the contours of all the seven continents seem to fit together like a jigsaw puzzle. He also noticed that rock types, geological structures & fossil plants on both sides of the Atlantic were similar.

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So, he suggested that once upon a time, there was a super-continent called Pangaea, which broke apart due to tectonic shifts of the Earth's plates, and different pieces moved away to form what are currently the seven continents!

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Of course, he was laughed away! Only after he died, and as more evidence piled up, the world finally accepted the continental drift theory! So, today we know that until 225 million years ago, dinosaurs roamed on the Pangaea!

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About 200 million years ago, Pangaea first split up into two large landmasses -the northern Laurasia (North America, Europe & parts of Asia) & the southern Gondwana (South America, Africa, Australia, India & Antarctica).The name Gondwana apparently comes from the Gond tribe of central India!

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Next, the Gondwana itself broke. India & Madagascar broke away, first from Africa & then from Australia-Antarctica & drifted northwards! Somewhereon the way, the intense tectonic shifts & the associated volcanic activity created the Deccan plateaus of peninsular India.

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Around 55 million years ago, the northwardly drifting Indian plate collided with the Eurasian plate and the Himalayan ranges were formed. That's why fossils of marine animals have been found high up in the Himalayan ranges! That's how the Indian sub-continent was formed!

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Similarly, Australia & Antarctica split up and drifted to their respective current positions. So, tectonically, India, Southeast Asia & Australia areon the same plate!

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And the huge mass of water with Africa on the east, Indian sub-continent on the north & Southeast Asia-Australia on the west, came to be formed & was called the Indian Ocean!

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Amazingly, this continental drift is still happening! Himalayas are apparently still rising at the rate of 5 mm every year! And the Indian Ocean region is still shaping up!

As a foot note to this story, sometime during this 200-million-year continental drift, the most dominant species on Earth, dinosaurs, got extinct & were replaced by another species, who evolved in the region of East Africa into what we today know as Homo Sapiens!