Excluding some monitor lizards that hiss when they feel threatened, or the grunt sounds made by some lizards during fights, geckos are the only species of lizards that actually make sounds. Lizards of the Gekkonidae make calls for a variety of purposes, such as establishing a social hierarchy, making territorial claims and mating communications. Like frogs, geckos will also call out for no reasons whatsoever when nightfall comes. However, not all Gekkonidae lizards make sounds. Geckos comprise a large portion of lizards in Taiwan , and the ubiquitous house geckos are the most common calling lizards. These lizards not only call out at nights, during the daytime, they also hide in the shades and emit loud “ zhe zhe zhe zhe” like sounds. Traditional Taiwanese folklore believed that “only lizards in the south call; those in the north don't.” Some suggested that this was based on geographical segregation caused by natural barriers like the Da-An River. In fact, this is a misconception mostly attributed to the difficulty of indentifying the many species of geckos in Taiwan . Without proper training, one would have a hard time noticing the subtle differences in their features. An example is the similarity between the common house gecko and the Bowring's gecko. The house gecko prefers hot climates; therefore it thrives mostly in Southern Taiwan , whereas the Bowring gecko prefers the more temperate climates of the North. Because house geckos emit very loud calls, the locals mistook them as “only the Southern lizards make calls.” Nowadays with advances in transportation, people can now migrate frequently between Northern and Southern Taiwan . As a result, the house geckos, who like to reside in human dwellings and furniture, gradually spread from the South to the North, and can be heard all island wide now.