Speaker
Description
Rising sea temperature poses a significant threat to marine fishes. While current-day populations of reef fish suffer when exposed short-term to elevated temperatures, future warming will occur over numerous generations for most species. Recent studies have shown that when parents experience warmer ocean conditions throughout life, offspring performance improves. Yet we do not know the mechanisms that underpin these transgenerational effects. For example, it is unknown if one or both parents facilitate the observed offspring improvement. Here, we determined what combination of parental experience (i.e. mothers, fathers, or both parents) and cue timing (during development and/or reproduction) is required to have beneficial effects on offspring performance at elevated temperature in the spiny damselfish, Acanthochromis polyacanthus. F1 offspring from wild-caught pairs were exposed to current-day or elevated temperatures (+1.5°C) during early development and/or reproduction. F1 breeding pairs were arranged so that every combination of male and female thermal experiences occurred. Interestingly, no breeding took place when both parents experienced elevated temperature during developmental and reproductive stages. F2 offspring from all the remaining parental combinations were reared for 3 months in current-day, intermediate (+0.75°C), or elevated (+1.5°C) temperatures to disentangle developmental versus transgenerational effects. We compared body size, mortality, swimming performance, and patterns of sex determination in F2 juveniles. This transgenerational experimental design represents a significant advancement in our understanding of how environmental conditions experienced in one generation influences the performance of the next generation and better predicts the resilience of coral reef fish to ocean warming.
