Why is the east coast of Madagascar so straight?
David Bortin
Whittier, California, US
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It was discovered about 10 years ago that, some 88 million years prior, the subcontinent of India and the island of Madagascar were neighbours in the ancient landmass called Gondwana. But plate tectonics makes for strange bedfellows, and it gave India the wanderlust to split off and elope with southern Asia, some 4800 km to the north.
The rapid split produced what is described as a 鈥渟craping鈥� action that left Madagascar鈥檚 east and (to a lesser, but still noticeable extent) India鈥檚 south-western shoreline remarkably straight.
The future remains to be seen by our successors billions of years from now, but it has been suggested by some that Madagascar might follow India. More likely is the prospect of Madagascar鈥檚 fragmentation.
Mustapa Osman
Singapore
The east coast of Madagascar is straighter partly because of consistent ocean currents and wave action from the Indian Ocean. Over millions of years, these forces have eroded the coastline in a more uniform way, making it appear straighter.
Unlike the west coast, which has more bays and river mouths that create a jagged appearance, the east coast of the country has fewer of these features, contributing to its straight look.
David Clarke
Seaford, East Sussex, UK
Madagascar is an example of the early work of Slartibartfast before he got into designing fjords.
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