... examples include:¹

After I. Abbott, as cited in [14]

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... assistance²

Of course, human activities that altered existing habitat in Britain may have made the introductions possible.

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... Wisconsin³

And presumably of many other glaciated regions in the North Temperate Zone

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... world.⁴

This is a theme I first touched on early in the course when we talked about the biology of human-caused extinctions.

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... occasionally 50mm.⁵

Drawn largely from [8]

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... St. Claire⁶

Lake lying between Lake Huron and Lake Erie.

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... Act.⁷

Its native habitat has been destroyed by past grazing and water-management practices in the parts of Arizona where it occurs.

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... we do?⁸

see [13] for a more complete discussion.

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... consequences.⁹

See [11,16].

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