Despite their somewhat silly appearance, the majority of pufferfish species are toxic and they are amongst the most poisonous vertebrates in the world. They are primarily found in tropical waters, although they are occasionally native to temperate zones as well.
Contrary to popular belief, the pufferfish's primary defensivemechanism is not its ability to expand. Instead, it has a uniquetail fin which can act as a rudder and provide the pufferfish withan exceptional burst of speed over short distances. When it sensesa predator about to strike, it will speed up and hopefully avoidharm. However, if this does not work the pufferfish will then suckeither air or water into its stomach. In doing so, it becomes morechallenging to attack due its increased size and outward facingtoxic barbs.