14 research outputs found

    Experimental nest cooling reveals dramatic effects of heatwaves on reproduction in a Mediterranean bird of prey

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    Future climatic scenarios forecast increases in average temperatures as well as in the frequency, duration, and intensity of extreme events, such as heatwaves. Whereas behavioral adjustments can buffer direct physiological and fitness costs of exposure to excessive temperature in wild animals, these may prove more difficult during specific life stages when vagility is reduced (e.g., early developmental stages). By means of a nest cooling experiment, we tested the effects of extreme temperatures on different stages of reproduction in a cavity-nesting Mediterranean bird of prey, the lesser kestrel (Falco naumanni), facing a recent increase in the frequency of heatwaves during its breeding season. Nest temperature in a group of nest boxes placed on roof terraces was reduced by shading them from direct sunlight in 2 consecutive years (2021 and 2022). We then compared hatching failure, mortality, and nestling morphology between shaded and non-shaded (control) nest boxes. Nest temperature in control nest boxes was on average 3.9 degrees C higher than in shaded ones during heatwaves, that is, spells of extreme air temperature (>37 degrees C for =2 consecutive days) which hit the study area during the nestling-rearing phase in both years. Hatching failure markedly increased with increasing nest temperature, rising above 50% when maximum nest temperatures exceeded 44 degrees C. Nestlings from control nest boxes showed higher mortality during heatwaves (55% vs. 10% in shaded nest boxes) and those that survived further showed impaired morphological growth (body mass and skeletal size). Hence, heatwaves occurring during the breeding period can have both strong lethal and sublethal impacts on different components of avian reproduction, from egg hatching to nestling growth. More broadly, these findings suggest that the projected future increases of summer temperatures and heatwave frequency in the Mediterranean basin and elsewhere in temperate areas may threaten the local persistence of even relatively warm-adapted species

    'There’s a bit of banter': How male teenagers 'do boy' on social networking sites

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    This chapter discusses teenage boys’ use of banter on social networking sites such as Facebook by presenting data collected via semi-structured interviews and focus groups with boys and girls aged 11-16 from three schools in England. For male teenagers utilising social networking sites, banter is a common form of social interaction within peer groups and is a means of othering, and of performing and constructing hegemonic masculinity. Banter is characterised by the use of confrontational exchanges used to explore social boundaries and values amongst friends, and is strongly involved in male bonding rituals. It is employed as a means of negotiating status and of in-group inclusion and out-group rejection. We present findings which focus on: male teenagers learning to banter; the relationship between banter and bullying; and how banter overflows into other distinct but related practices
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