Indigenous and introduced Collembola differ in desiccation resistance but not its plasticity in response to temperature.

Biological invasions have significant ecological and economic impacts. Much attention is therefore focussed on predicting establishment and invasion success. Trait-based approaches are showing much promise, but are mostly restricted to investigations of plants.

Basal resistance enhances warming tolerance of alien over indigenous species across latitude.

Soil systems are being increasingly exposed to the interactive effects of biological invasions and climate change, with rising temperatures expected to benefit alien over indigenous species. We assessed this expectation for an important soil-dwelling group, the springtails, by determining whether alien species show broader thermal tolerance limits and greater tolerance to climate warming than their indigenous counterparts. We found that, from the tropics to the sub-Antarctic, alien species have the broadest thermal tolerances and greatest tolerance to environmental warming.

Protein synthesis rates in Drosophila associate with levels of the hsr-omega nuclear transcript.

Transcripts of the Drosophila hsr-omega gene are known to interact with RNA processing factors and ribosomes and are postulated to aid in co-ordinating nuclear and cytoplasmic activities particularly in stressed cells. However, the significance of these interactions for physiological processes and in turn for whole-organism fitness remains an open question. Because hsr-omega's cellular expression characteristics suggest it may influence protein synthesis, and because both genotypic and expression variation of hsr-omega have been associated with thermotolerance, we characterised 30 lines for variation in the rates of protein synthesis, measured in ovarian tissues, both before and after a mild heat shock, and for basal levels of the two main hsr-omega transcripts, omega-n and omega-c.

Costs and benefits of cold acclimation in field-released Drosophila.

One way animals can counter the effects of climatic extremes is via physiological acclimation, but acclimating to one extreme might decrease performance under different conditions. Here, we use field releases of Drosophila melanogaster on two continents across a range of temperatures to test for costs and benefits of developmental or adult cold acclimation. Both types of cold acclimation had enormous benefits at low temperatures in the field; in the coldest releases only cold-acclimated flies were able to find a resource.

Clinal variation in Drosophila serrata for stress resistance and body size.

Clines for size and stress resistance traits have been described for several Drosophila species and replicable clines across different species may indicate climatic selection. Here we consider clines in stress resistance traits in an Australian endemic species, D. serrata, by comparing levels of variation within and among isofemale lines initiated with flies collected from the eastern coast of Australia.