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Predicting insect responses to global climate change involves understanding cross-generation effects of temperature. The majority of temperate insects overwinter in a state of diapause, a pre-emptive response to winter conditions associated with increased cold hardiness. Diapause is often induced following maternal adult detection of an environmental cue signifying the onset of winter, whilst diapause is initiated in a subsequent life stage and/or generation. Continued global warming will expose adults to higher late-autumn temperatures, whilst diapause life stages will still experience prolonged winter cold. The cross-generation effect of temperature was investigated by acclimating adult Calliphora vicina to present-day (15°C) and future (20°C) late-autumn conditions and assessing cold-hardiness in diapause (D15 and D20) and nondiapause (ND15 and ND20) progeny. A cross-generation plasticity in cold hardiness was associated with D but not ND larvae. D15 larvae exhibited an enhanced ability to suppress internal freezing (supercooling point=-18.9±0.9°C) compared with D20 (−15.3±0.8°C), and displayed a greater tolerance of prolonged exposure to −4°C (LT 50 =26.0±1.0 and 11.4±1.1 days, respectively) and −8°C (5.1±1.1 and 3.0±1.1 days, respectively). These changes were associated with a reduced glucose content in D15 (2.4±0.3 g mg −1 ) compared with D20 (3.0±0.3 g mg −1) larvae. In conclusion, C. vicina adults exposed to warmer autumn conditions during diapause induction will produce larvae with a reduced cold hardiness capacity, which could negatively impact winter survival. Given that maternal regulation of diapause is common among temperate insects, this could be a widespread phenomenon. KEY WORDS: Insect, Diapause, Cross generation, Cold hardiness, Climate change INTRODUCTIONInsects residing within the temperate zone experience yearly winter cycles of low temperatures, potentially freezing conditions and limited nutrient availability. To enhance the chances of survival during this period, insects either migrate to more favourable locations, which offer sufficient resources for growth and reproduction, or remain in situ, where physiological and biochemical adaptations are implemented to assist winter survival (Tauber and Tauber, 1976;Danks, 1987;Danks, 2002). The majority of temperate insects utilise the latter approach and enter a dormant state called diapause (Denlinger and Lee, 2010). Diapause is a genetically programmed, pre-emptive response to adverse environmental RESEARCH ARTICLESchool of Biosciences, University of Birmingham, Birmingham B15 2TT, UK. conditions (Denlinger, 2002), which synchronises active life stages with more favourable conditions and enhances winter survival (Danks, 2002; Hahn and Denlinger, 2007).Diapause can be either obligatory or facultative (Tauber et al., 1986). Obligatory diapause occurs at a specific stage in the life cycle irrespective of prevailing environmental conditions, while facultative diapause is induced following detection of specific environmental cues (Denlinge...

Highlights The relationship between obesity and exposure to food advertising meets all criteria commonly used to demonstrate the presence of a causal relationship in epidemiology. Younger children (≤8 years of age) are more susceptible to the impacts of food marketing, in terms of quantity and quality of calories consumed, than older children and adults, although emerging evidence suggests that adolescents (10–19 years) may be most susceptible to the impacts of online advertisements. Children from socio-economically disadvantaged and ethnic minority backgrounds are disproportionately exposed to unhealthy food advertisements. Statutory regulation is a potentially cost-effective policy option, in terms of healthcare savings outweighing the costs of implementing the policy. However, advertising restrictions must be accompanied by community-based interventions that address other causes of poor diet and sedentary behaviour; this is because online and TV advertisements represent one small dimension in the wider obesogenic environment. Voluntary bans are ineffective. Exposure to unhealthy food advertising is similar before and after the introduction of voluntary food advertisements.