The World’s Six Smallest and Deadliest Animals

The sprightly and brightly colored frog may look enchanting, but it can produce enough poison to kill 10 humans. Thriving in humid, tropical environments of Central and Latin America, the poison dart frog oozes black slime from its back, which is actually a neurotoxin used to ward off predators.

Found across the northern half of Australia – particularly in Queensland – the box jellyfish washes up on the shores after heavy rain and high tide. If stung, the venom contained in their tentacles attacks a human’s cardiac and nervous system – even when the tentacles aren’t attached to the jellyfish’s body. Immediate treatment is necessary to prevent death.

While extremely irritating, mosquitoes are also extremely dangerous. Mosquito-borne diseases include yellow fever, dengue fever and malaria, which account for the death of two million people every year.