Life‐stage specificity and cross‐generational climate effects on the microbiome of a tropical sea urchin (Echinodermata: Echinoidea)

Abstract

Microbes play a critical role in the development and health of marine invertebrates, though microbial dynamics across life stages and host generations remain poorly understood in most reef species, especially in the context of climate change. Here, we use a 4‐year multigenerational experiment to explore microbe–host interactions under the Intergovernmental Panel on Climate Change (IPCC)‐forecast climate scenarios in the rock‐boring tropical urchin Echinometra sp. A. Adult urchins (F0) were exposed for 18 months to increased temperature and pCO2 levels predicted for years 2050 and 2100 under RCP 8.5, a period which encompassed spawning. After rearing F1 offspring for a further 2 years, spawning was induced, and F2 larvae were raised under current day and 2100 conditions. Cross‐generational climate effects were also explored in the microbiome of F1 offspring through a transplant experiment. Using 16S rRNA gene sequence analysis, we determined that each life stage and generation was associated with a distinct microbiome, with higher microbial diversity observed in juveniles compared to larval stages. Although life‐stage specificity was conserved under climate conditions projected for 2050 and 2100, we observed changes in the urchin microbial community structure within life stages. Furthermore, we detected a climate‐mediated parental effect when juveniles were transplanted among climate treatments, with the parental climate treatment influencing the offspring microbiome. Our findings reveal a potential for cross‐generational impacts of climate change on the microbiome of a tropical invertebrate species.

Negative parental and offspring environmental effects of macroalgae on coral recruitment are linked with alterations in the coral larval microbiome

“…lipids, amino acids) is reduced in eggs of heat-stressed parents in soft corals [33]. In addition, parents could differentially invest in their offspring by vertically transmitting distinct Symbiodiniaceae [30] and prokaryotic communities [5,34]. So far, negative parental effects in corals and other marine invertebrates, such as urchins, have essentially been demonstrated relative to climate-associated stressors [32][33][34].…”

“…In addition, parents could differentially invest in their offspring by vertically transmitting distinct Symbiodiniaceae [30] and prokaryotic communities [5,34]. So far, negative parental effects in corals and other marine invertebrates, such as urchins, have essentially been demonstrated relative to climate-associated stressors [32][33][34]. Yet, given that macroalgae can alter both health and fecundity of corals, one might expect that negative parental effects relative to algal competition might jeopardize coral recruitment success.…”