North America is currently experiencing an unprecedented and rapid loss of species. What is believed to be the main trigger of such events, either directly or indirectly?
A) continental drift B) increased human population C) climate change D) increased predation by wild carnivores
Purple loosestrife, Lythrum salicaria, is a beautiful, long-stemmed wetlands species brought to the United States from Europe as an ornamental plant. In the United States, it has no predators and crowds out cattails, Typha latifolia, another wetlands plant that's a valuable resource for many species. Purple loosestrife is an example of
A) an introduced species. B) a parasite. C) a predator. D) overexploitation.