FROGS

The golden poison frog (Phyllobates terribilis) is the most poisonous frog known to us, and it's considered to be one of the most poisonous animals in the world. This frog's poison is found in their skin, making them too toxic to touch. While most species are considered toxic but not deadly, they are distasteful to a predator and can even be fatal. The poison can cause serious swelling, nausea and muscular paralysis.

Its poison is a neurotoxin known as batrachotoxin (the chemical around the yellow frog's tongue). The word is from Greek for 'frog' and 'toxin' and it's more lethal than tetrodotoxin, the poison from pufferfish. An average golden poison frog contains enough batrachotoxin to kill ten adult humans. To represent this information I initially thought of drawing ten distinct objects that adults use; I couldn't execute the idea due to space. I resolved this by drawing ten lights floating around; one could be philosophical and say that the coloured light dots represent the spirits of the killed adults. The different colours can also signify the different personalities; these frogs don't look at any specific characteristic when killing. My A level Biology teacher said that the coloured light dots looked like skin cells.

Batrachotoxin acts as a poison by preventing the sodium ion channels of nerve and muscle cells from closing, which causes interference in the nerve signal to muscles. This causes paralysis, and then death. You can see that the chemical is physically blocking the purple sodium ion channel at the top of the page.

Golden poison frogs are at no risk of poisoning themselves, as they have evolved to have a mutated sodium ion channel protein. The substitution of a single amino acid within the ion channels protein from asparagine (the one on the ground near the brown light; it's the amino acid us humans have) to threonine (the one on the yellow frog) seems to allow the protein channel to remain fully functional, being unaffected by batrachotoxin.

Other frogs also contain this toxin, such as kokoe poison frog (Phyllobates aurotaenia), but not in such high levels. The golden frog is much bigger in size than the black one to show this piece of information.

Interestingly, batrachotoxin is not produced by the frogs themselves but is acquired through their diet. In captivity, batrachotoxin containing frogs can become totally harmless. It is thought that the frogs obtain the compound by eating certain mites, beetles and ants that contain batrachotoxin.