Evolution
of the Landscape as the Result of Deglaciation
From the book Le
fleuve aux grandes eaux
During the 100,000-year-long Ice Age that formed the glaciers,
the continent sank several dozen metres under the weight
of an ice sheet more than 2,000 metres thick.
The melting ice caused sea levels to rise 120 metres.
The settling of the Earth's crust, gradually relieved
of the pressure of the ice, slowed.
Salt water submerged the land, and marine animals moved
into regions
that had been inaccessible before. The continent stopped
sinking.
The continent rose up again. The land that emerged was
first colonized by birds, pinnipeds, lichens and leafy
plants.
The rising land mass isolated populations of fish and
seals. The vegetation attracted new animal species.
The upward movement of the continent slowed.
Varieties of trees and plants grew more numerous and diversified.
The rich flora and fauna adapted to the new territory
attracted predators and hunter-gatherers.
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