Desiccation Resistance in Four Drosophila Species: Sex and Population Effects

Abstract

Desiccation resistance and body mass were measured in multiple populations of each of four species of Drosophila: two desert endemic species (D. nigrospiracula and D. mojavensis), and two with more widespread distributions (D. melanogaster and D. pseudoobscura). While flies from the desert species were more desiccation tolerant, there was, in certain cases, significant variation in desiccation resistance among populations of the same species. A significant difference in desiccation resistance was observed between the sexes, females were more resistant than males, but this relationship was reversed when taking into account body mass differences between the sexes. The degree of observed within-species variability demonstrates that studies focusing upon differences between species can produce different conclusions if they rely on observations for only single populations of a given species. Our data also suggest the existence of multiple mechanisms for desiccation resistance.

Repeated bouts of dehydration deplete nutrient reserves and reduce egg production in the mosquito Culex pipiens

“…Studies with Drosophila demonstrate higher dehydration resistance (Gibbs and Matzkin, 2001;Matzkin et al, 2007), reduced water loss rates (Gibbs and Matzkin, 2001) and reduced metabolism in xeric-adapted species (Gibbs et al, 2003). Selection for dehydration tolerance in D. melanogaster is associated with the accumulation of glycogen and differential metabolism of carbohydrates and lipids (Djawdan et al, 1998;Bradley et al, 1999;Gibbs, 2002).…”

Transcriptional Regulation of Metabolism Associated With the Increased Desiccation Resistance of the Cactophilic Drosophila mojavensis

“…Within the genus Drosophila many species have adapted to the desert. One such example is D. mojavensis, a cactophile more resistant to desiccation than all of its congeners (van Herrewege and David 1997; Gibbs and Matzkin 2001;Matzkin et al 2007). D. mojavensis can survive for long periods in low humidity because of an overall reduction in metabolic rate and discontinuous gas exchange (Gibbs 2002;Gibbs et al 2003b;Marron et al 2003).…”

“…Xeric-adapted Drosophila species have responded to these challenges with high desiccation resistance (Gibbs and Matzkin 2001;Matzkin et al 2007), lower water loss rates (Gibbs and Matzkin 2001), and lower metabolic rates under dry conditions (Gibbs et al 2003b). Additionally, artificial selection experiments in Drosophila melanogaster suggest that increased desiccation resistance affects both metaExpression data from this article have been deposited in the Gene Expression Omnibus under series entry no.…”

“…D. mojavensis is a cactophilic fly inhabiting the deserts of North America. Adaptation to its xeric habitat includes extreme desiccation resistance and the ability to reduce respiration rate or water loss rate under desiccating conditions (Gibbs and Matzkin 2001;Gibbs et al 2003b;Matzkin et al 2007). The relative humidity experienced by D. mojavensis in the field can be as low as 8%, although it can fluctuate depending on the time of day and location on the host (Gibbs et al 2003c).…”

Desiccation tolerance as a function of age, sex, humidity and temperature in adults of the African malaria vectorsAnopheles arabiensisPatton andAnopheles funestusGiles

“…Such a response has not been documented across a wide variety of insect groups, except for several species of Drosophila, and even here variation is typically among early and late life and also among species and sex (e.g. Matzkin et al, 2007;Shahrestani et al, 2012;Parkash and Ranga, 2013;Aggarwal, 2014). Mechanisms that might underlie a decline in tolerance with age are thought to include changes in WLR, probably a function of variation in cuticular hydrocarbon content and composition, melanization, differences in initial body water content and tolerance of dehydration (Nghiem et al, 2000;Gibbs and Markow, 2001;Benoit and Denlinger, 2007;Weldon et al, 2013).…”