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Gondwanaland
In 1885 Eduard Suess
(1831-1914), Austrian geologist, realized that there had once been a
land bridge between South America, Africa, India, Australia, and
Antarctica. He based his deductions upon the fossil fern Glossopteris,
which is found throughout India, South America, southern Africa,
Australia, and Antarctica. He named this large land mass Gondwanaland
(named after a district in India where the fossil plant Glossopteris
was found).
In 1912 Alfred Lothar
Wegener (1880-1930) presented his hypothesis of continental drift, and
published it The Origin of the Continents and Oceans. He suggested
that originally there was a single land mass, Pangaea, surrounded by a
single world-wide ocean, Panthalassa. About two hundred million years
ago Pangaea began to break up, and after twenty million years two
continents, Lauasia and Gondwanaland, separated by the Tethys Sea
emerged, together with other continental fragments. Thermal convection
in the earth’s mantle in the mid-Atlantic caused the sea floor to
spread and contributed to the drift of the continents. They continued
to drift until they assumed the present configuration.
The stamps issued by the British Antarctic Territory
show the drift of Gondwanaland from 280 million years ago to the
present, and life forms from those periods.
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