sparrow's range. Both birds of a pair incubate the eggs during the day, switching every ten or fifteen minutes. At night, only the female incubates the eggs, while the male roosts outside or in the nest. In pairs breeding outside of colonies, birds leave the nest to make room for their mates upon hearing their mates approaching. Among colonial pairs, the incubating bird waits until its partner arrives in the nest, to prevent other birds from entering the nest. Incubation seems to begin before the clutch is complete, and lasts 12–24 days. The young of a clutch hatch over two or three days and are brooded until their feathers develop and eyes open five days after hatching. The young are fed on insects until they fledge 16 to 25, typically 17, days after hatching. After this they are fed for one or two weeks. While feeding nestlings, the female is dominant over the male. Cape sparrows are among the main hosts of brood parasitism by the dideric cuckoo in southern Africa, and sometimes parasitise nests of their own species. Relationships with humans The Cape sparrow is an abundant and familiar bird of human habitations and cultivation in most of southern Africa. It is not believed to be threatened, and accordingly is listed as a species of least concern on the IUCN's Red List. It can be an agricultural pest, especially of grain cultivation and vineyards. When vineyards in the south-west Cape started letting weeds grow between vines to conserve moisture, around 1956, the Cape sparrow moved in. Cape sparrows quickly exhausted the seeds and started eating the grapes. The Cape sparrow is now a serious pest in vineyards. Vineyards are not an optimal habitat, and some populations have had such a low reproductive success that they could not be maintained without immigration. The Cape sparrow was featured on the lowest-denomination South African coin, from the farthing (¼-cent) in 1923 to the cent that ceased to be minted in 2002, with designs based on an original by George Kruger Gray. This was said to be because women interned at a concentration camp in Bethulie during the Boer War adopted a biblical quotation (from Matthew 10) as their motto: "Are not two sparrows sold for a farthing? and one of them shall not fall on the ground without your Father." It has also been featured on stamps from Lesotho and the Central