Island dwarfism in a tropical Australian python (Simalia amethistina)

Dwarfism in insular populations of snakes has been documented at several localities around the world and it has been largely attributed to a phenotypic response of these isolated populations to food availability and composition. The incidental collection of size data for the Milman Island population of Simalia amethistina in north Queensland has brought to light a previously unknown example of island dwarfism in a tropical python species in Australia. Simalia amethistina on Milman Island are significantly smaller than conspecifics from the nearby mainland, with the maximum recorded size being only as large as the smallest 50% of mainland specimens. We attribute this dwarfism to the lack of large-bodied prey species available on Milman Island.