Evaporative water loss (EWL) occurs principally across the skin (cutaneous water loss, CWL) of terrestrial reptiles (Shoemaker and Nagy, 1977; Mautz, 1982), but EWL also occurs across respiratory passages (respiratory water loss) and the eyes (ocular water loss) (Mautz, 1982). Over 70% of EWL in agamid lizards is from CWL (Eynan and Dmi’el, 1993). The factors determining the rate of CWL are ski...

drought stress is the most important factor that reduces yield in crops including chickpea and causes some changes in seed composition. this study was performed in order to evaluate the effects of drought stress and starter nitrogen fertilizer on four cultivars of chickpea. experiment was performed in a split-factorial using randomized complete block design with three replications. drought stre...

We have investigated water loss from, and ion regulation within, the hemolymph and tissues of five replicate populations of Drosophila melanogaster that have undergone laboratory selection for enhanced desiccation resistance (i.e. the D populations). We compared the patterns and rates of water loss and the ion content of the D populations prior to and during desiccation with those of five repli...

Water-loss rates increase after mating in queens of the harvester ant Pogonomyrmex barbatus (Formicidae: Myrmicinae), then increase again after the mated queens excavate an incipient nest. We determined the mechanistic basis for these increased water-loss rates by examining cuticular permeability, respiratory water loss, metabolic rates, and cuticular hydrocarbons for queens at three stages in ...

The osmoregulatory and respiratory responses of male and female Smeringurus mesaensis (Vaejovidae) to prolonged desiccation were measured. No significant effect of sex on mass-loss rates (MLRs) was found. Still, females maintained their haemolymph osmolality when desiccated to 10% mass loss, whereas that of males increased significantly after loss of as little as 5% of initial mass. Females had...

We measured CO2 and H2O release from individual fruit flies from five populations of Drosophila melanogaster selected for resistance to desiccation (D flies). Our previous work found that these flies survive for an extended period in dry air, have an increase in the peak height and frequency of CO2 release, as measured by the standard error of a linear regression (SER) of CO2 release for the en...

Insects breathe through valved openings (spiracles) in their cuticle. Many insects open and close their spiracles in a cyclic pattern (discontinuous gas-exchange cycles, or DGC). These cycles were observed over half a century ago, their hypothesized function being to minimize loss of water from the tracheal system. However, numerous recent studies have found that respiration accounts for a smal...

Flowers face desiccating conditions, yet little is known about their ability to transport water. We quantified variability in floral hydraulic conductance (Kflower ) for 20 species from 10 families and related it to traits hypothesized to be associated with liquid and vapour phase water transport. Basal angiosperm flowers had trait values associated with higher water and carbon costs than monoc...

in order to investigate the effect of water stress at heading stage on grain yield and yield components of eight wheat cultivars, in 2008 year a research was conducted in the two regions esfahan and ardestan by using split plot in a randomized complete block design with three replications which that two irrigation treatments included custom and late season water stress were main factor and 8 wh...

BACKGROUND Research on variation in bill morphology has focused on the role of diet. Bills have other functions, however, including a role in heat and water balance. The role of the bill in heat loss may be particularly important in birds where water is limiting. Song sparrows localized in coastal dunes and salt marsh edge (Melospiza melodia atlantica) are similar in size to, but have bills wit...