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7 tiny but deadly creatures

By: Bryan Nelson on Sept. 25, 2013, 5:43 p.m.
A blue-ringed octopus

Photo: Angell Williams/Flickr

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Blue-ringed octopus

Though extremely small (adults only grow to about 5 centimeters in size), the blue-ringed octopus is widely considered to be one of the world's most venomous creatures. They're docile by nature, but they will bite if agitated or accidentally stepped on at the beach. No antivenom currently exists for their bite.