Temperature, urbanization and body color polymorphism in South Brazilian populations of Drosophila kikkawai (Diptera, Drosophilidae)

Abstract

Body color polymorphism of urban populations of cosmopolite fly Drosophila kikkawai Burla, 1954 was investigated in relation to its possible association with environmental temperature. Samples of D. kikkawai were collected in spring, summer, autumn and winter between 1987 to 1988, in zones with different levels of urbanization in the southern Brazilian city of Porto Alegre, Rio Grande do Sul. A clear association was observed between darker flies and both seasons with low temperatures and areas of low urbanization (where temperature is generally lower than in urbanized areas). Results of preliminary laboratory experiments involving six generations of flies grown in chambers at temperatures of 17 o and 25 o C confirmed this tendency to a relationship between body color and temperature, with allele frequency of the main gene involved in body pigmentation changing over time.

The genetic basis of adaptive pigmentation variation in Drosophila melanogaster

“…For example, 'black' and 'brown' morphs of Drosophila elegans occur in different parts of this species' range (Hirai & Kimura 1997). In Drosophila kikkawai from Brazil, darker individuals were found in cooler seasons and habitats (Da Costa et al . 2003).…”

Phylogeny and taxonomic revision of all genera of Conopidae (Diptera) based on morphological data

“…Colour of body structures is often employed in identification keys and phylogenetic analyses of insects. Even highly distinctive coloration, however, can be highly variable within some species of Diptera (Holloway, ; Costa, Rohde & Valente, ). Instances have been recorded where coloration is dependent on season and temperature (Costa et al ., ; Martín‐Vega & Baz, ).…”

“…Even highly distinctive coloration, however, can be highly variable within some species of Diptera (Holloway, ; Costa, Rohde & Valente, ). Instances have been recorded where coloration is dependent on season and temperature (Costa et al ., ; Martín‐Vega & Baz, ). This is particularly emphasized in species with wide geographical ranges (Holloway, ).…”

Identification key for drosophilid species (Diptera, Drosophilidae) exotic to the Neotropical Region and occurring in Brazil

“…The oriental species D. kikkawai supports a cosmopolitan status (Pinheiro and Valente, 1993), but it is not clear when it was introduced in South America and Africa and nor if this process was mediated by humans (Ashburner, 1989). In Brazil, this species is found in both natural (Sene et al, 1980) and urban environments (Costa et al, 2003), usually in low abundances (but see Cavasini et al, 2014).…”