naturally changing, it is difficult to gauge the extent of change caused by pastoralisation, however, grazing by livestock is considered incompatible with natural succession of ecosystems. Overgrazing by livestock causes alteration and degradation of soil and flora. Very few arid species have been recorded as declining in numbers since European settlement and some species, including the Spinifex pigeon and the Crested pigeon have increased in population size, possibly due to the increase in permanent water sources created for livestock Cultural links Species within the Geophaps have been named in Aboriginal stories and songs. The Partridge pigeon (Geophaps smithii) has been listed as a bird species which features as a Morrdjdjanjno song subject. Morrdjdjanjno is a genre of song from the Arnhem Land plateau in the Northern Territory top end, they are sung only by men and passed down as 'open domain' songs. Morrdjdjanjno songs' subjects are discussed in relation to mythological events of religious significance and are believed to bring the singer into contact with the animal being sung about or to increase numbers of certain species. The Spinifex pigeon and Crested pigeons have been recorded in versions of an Aboriginal Children's story from Central Australia, conveying rich symbolic meanings between the Geophaps species and associations by the Arandic people with 'kurdaitchas' (a person who sets out to kill or harm someone, often in revenge, and who leaves no trace. References Bird genera Taxa named by George Robert Gray