INVADERS: Strange Days on Planet Earth
A team of investigators is on the trail of plants and animals that are turning up where they don�t belong. Their work is part of an increasingly urgent global quest. Alien species have invaded every continent, and they are spreading disease and devouring buildings. We've built a global system that transports plants and animals along with other cargo. Scientists are trying to figure out what this movement of plants and animals means. Worldwide, invasive species are already the second greatest cause of extinction behind habitat destruction. Researchers see the potential for a dark outcome: extinction on an epic scale.
