The Amazon is a forest that covers most of the Amazon River Basin in South America. It is the largest Rain Forest on Earth and covers around 40% of the South American continent; seven million square kilometres (1.7 billion acres). It is believed that the oldest parts of the forest are Eocene (55.8Ma) in age.
With several environmental changes across the forest, as well as human influence, the forest is made up of many different ecosystems including: rainforest; deciduous forest; seasonal forest; Savannah and flood plains (from the Amazon River).
The Amazon River is the second largest in the world and is comprised of some 1100 tributaries, 17 of which exceed 1500km in length. Originally the Amazon River flowed westwards, but around 15 million years ago, with the original uplift of the Andes (from the collision between the Nazca plate and the South American Plate) it became a vast, shallow inland sea, with fossils showing species similar to those found in the Pacific Ocean. Gradually the inland sea became a swamp-like fresh water lake, and then around one million years ago, water broke through on the west-hand side of this inland lake. The River began to flow east (as it does today); it was during this time that the rainforest that we know today was "born". During the last ice age, it is widely believed that the rainforest largely became "islands" of Savannah within the forest. It is thought that this separation of species, followed by their reintroduction to each other when the savannah returned back to forest, has contributed to the vast genetic diversity of the forest.
With several environmental changes across the forest, as well as human influence, the forest is made up of many different ecosystems including: rainforest; deciduous forest; seasonal forest; Savannah and flood plains (from the Amazon River).
The Amazon River is the second largest in the world and is comprised of some 1100 tributaries, 17 of which exceed 1500km in length. Originally the Amazon River flowed westwards, but around 15 million years ago, with the original uplift of the Andes (from the collision between the Nazca plate and the South American Plate) it became a vast, shallow inland sea, with fossils showing species similar to those found in the Pacific Ocean. Gradually the inland sea became a swamp-like fresh water lake, and then around one million years ago, water broke through on the west-hand side of this inland lake. The River began to flow east (as it does today); it was during this time that the rainforest that we know today was "born". During the last ice age, it is widely believed that the rainforest largely became "islands" of Savannah within the forest. It is thought that this separation of species, followed by their reintroduction to each other when the savannah returned back to forest, has contributed to the vast genetic diversity of the forest.
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