Nidoran are poisonous little creatures. They have 2 distinct evolution appearances. This is shown by what sex they are.
The males are a pinker color compared to the female which make them stand out a lot more in the forest, but despite lack of camouflage their bright colors show potential predators that they are highly poisonous.

They have barbs, similar to thick porcupines needles, but are not as tightly packed. They blend in with their skin so that predators cannot distinguish them and identify the non poisonous areas.
Nidoran actually have very curious natures and bond well with humans at a young age. Their poison cannot kill a human but can make them quite ill with symptoms similar to food poisoning.

They live mainly in thick forest and feed on things such as berries and shrubs. Despite their stumpy looking legs they are very fast and are hard to catch if you startle them.

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