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Buzzoni, D.

Publications and source records attributed to Buzzoni, D..

2 recordsLinked to original sources

Unexpectedly high coral heat tolerance at thermal refugia

Marine heatwaves and mass bleaching have led to global declines in coral reefs. Corals can adapt, yet, to what extent local variations in thermal stress regimes influence heat tolerance and adaptive potential remains uncertain. Here we identify persistent local-scale thermal refugia and hotspots among the reefs of a remote Pacific archipelago, based on 36 years of satellite-sensed temperatures. Theory suggests that hotspots should promote coral heat tolerance through acclimatisation and directional selection. While historic patterns of mass bleaching and marine heatwaves align with this expectation, we find a contrasting pattern for a single species, Acropora digitifera, exposed to a marine heatwave experiment. Higher heat tolerance at thermal refugia (+0.7 {degrees}C-weeks) and correlations with other traits suggest that non-thermal selective pressures may also influence heat tolerance. We also uncover widespread heat tolerance variability, indicating climate adaptation potential. Compared to the least-tolerant 10% of the A. digitifera population, the most-tolerant 10% could withstand an additional heat stress of 5.2 and 4.1 {degrees}C-weeks for thermal refugia and hotspots, respectively. Despite expectations, local-scale thermal refugia can harbour higher heat tolerance, and mass bleaching patterns do not necessarily predict species responses. This has important implications for designing climate-smart initiatives to tackle global-scale adaptive management problems.

ecology↗

Influences of male age, mating history and starvation on female post mating aggression and feeding in Drosophila

O_LIMating changes female behaviour and physiology across a wide range of taxa, with important effects for male and female fitness. These changes are often induced by components of the male ejaculate, such as sperm and seminal fluid proteins. C_LIO_LIHowever, males can vary significantly in their ejaculates, due to factors such as age, mating history, or nutritional status. This male variation may therefore lead to variation in the strength of responses males can stimulate in females, with alterations in fitness outcomes for both sexes. C_LIO_LIUsing the fruit fly, Drosophila melanogaster, we tested whether three aspects of male condition shape an important, but understudied, post-mating response - increased female-female aggression. C_LIO_LIWe found that females mated to old males fought less than females mated to young males. This effect was exacerbated in mates of old, sexually active males, but there was no effect of male starvation status on mating-induced female aggression. There was also a significant effect of age and mating history on female post-mating feeding duration. C_LIO_LIOur results add to a growing body of literature that variation in male condition can shape sexual selection through post-mating responses in females, including female-female interactions. Studying such variation may therefore be useful for understanding how the condition of sex affects the behaviour of the other. C_LI

animal behavior and cognition↗