European explorers like Captain Cook encountered pot-bellied, short-legged poi dogs that freely associated with hogs in the village. The dogs had very short hair that could come in any color, but brown poi dogs were regarded as distinct enough to warrant a specific name. The dogs also had peculiarly flattened heads. The latter trait is sometimes ascribed to the diet of the dogs in some unspecified way. Considering that poi does not require chewing, the dogs might have lost the need to maintain strong temporalis muscles; a reduced temporal fossa will cause a dog's head to appear flattened. Poi dogs were considered rather dim-witted and sluggish – any good hunting dog with acute senses would neither make a good poi dog nor be particularly useful on the islands – however, the dogs were strong-willed and not easily commanded.