#7 – Poison Dart Frog
The 2-inch long Poison Dart Frog lives in rainforests of Central and South America. You will also be amazed to know that only 2 micrograms of its lethal toxin is enough to kill 20 adult humans or 10,000 mice or other small mammals. The Poison Dart Frog stores the poison on its skin which can kill anyone who ingests it.