HOW HAVE SPECIES RANGES CHANGED OVER INDUSTRIAL TIMES?
Many species ranges have shifted dramatically during the last several hundred years, as the industrial activities of man have rapidly altered historical landscapes. This example depicts the differences between the historical (combined yellow and orange) distribution and current (orange) distribution of the grizzly bear, Ursus arctos horribilis, based on information from the Alberta Sustainable Resource Development Agency. By mapping the current and historical distributions, we can easily visualize the drastic range contraction of these iconic animals, which ranged all the way into mainland Mexico only 100 years ago! The dots represent specimen localities and dates obtained from the Global Biodiversity Information Facility. The projection used is the North American Albers Equal Area Projection, selected on purpose to avoid over-sizing Alaska , which could otherwise produce a false impression of the current distribution.
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