Large temporal variations of species composition and structure are common in communities composed of short-life organisms such as zooplankton. However, few studies have examined if dominant factors affecting the community composition and structure differ depending on time scales such as inter-annual, inter-seasonal and intra-seasonal scales. In this study, we examined the temporal -diversity of a zooplankton community for nine years to clarify if the relative importance of abiotic and biotic factors regulating the zooplankton community varies depending on the temporal scales. The analysis of temporal -diversity at various temporal scales with environmental variables showed that water temperature was a prime factor regulating the inter-seasonal variations of the community structure, while algal food conditions were more important in the intra-seasonal variations. Algal food conditions were also important for the variation in the community structures in the same month but different years. Temporal dissimilarity in terms of body size tended to be larger in inter-annual scale than inter-seasonal scale, suggesting that predation pressure can be a factor explaining temporal variations of the zooplankton community over a single year. These results show that the relative importance between biotic and abiotic factors regulating the zooplankton community change depending on the temporal scales examined.

Environmental variability drives adaptive responses, yet how organisms with minimal genetic diversity adapt remains unclear. Using invasive Daphnia pulex (JPN1 lineage), we demonstrate that phenotypic integration—coordinated trait expression—mediates environmental adaptation despite limited genetic divergence. We found that environment-dependent integration drives stress adaptation more strongly than genetic distance, with differential plasticity dynamically reorganizing trait correlations. Notably, digestive enzymes (particularly lipase) and body size showed tightly coordinated responses to resource limitation, revealing how phenotypic networks reorganize under stress. By developing a quantitative framework to track these genotype-environment interactions, we show how integration facilitates adaptation in genetically impoverished populations. These results challenge the paradigm that genetic divergence is essential for phenotypic adaptation and provide mechanistic insights into invasion success. Our approach bridges invasion biology and eco-evolutionary theory, offering predictive tools for understanding rapid adaptation in diverse asexual systems facing environmental change.