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Photographs: © Pal Teravagimov/Shutterstock (starling); © Injun/Shutterstock (fire ant); Danny E. Hooks/Shutterstock (kudzu); © Yulia Podlesnova/Shutterstock (cat); © Nikita Tiunov/Shutterstock (water hyacinth); © David Hancock/Shutterstock (cane toad); © John Wollwerth/Shutterstock (comb jelly); © Ronald Wittek/Age Fotostock (nutria); © David Cappaert (emerald ash borer).
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