Plant and Animal Species Becoming Extinct at Record Pace, Says U.N.

Source: CBS News - ScienceBoots dusty, lungs heaving, Dr. John Wiens searched the boulders of a desolate Arizona mountaintop for the last survivors of a 3-million-year-old lizard population — then said the words that both confirmed his life's work and broke his heart. "They're not there," he said. "It seems like the species is now extinct." The loss of plant and animal species on Earth is happening at a speed never seen in human history, according to the United Nations.