Key advances: global plankton biogeographic provinces, temperature- and circulation-driven structuring across domains of life, recognition of the Arctic Ocean as a distinct and internally structured marine biome.
Tara Oceans has established a new framework for understanding marine plankton biogeography at global scale, demonstrating that plankton communities are structured by a combination of environmental gradients, ocean circulation, and organismal traits rather than simple dispersal limitation. Across all domains of life, analyses revealed coherent, size-dependent biogeographic provinces spanning ocean basins, with temperature emerging as a dominant driver of surface-ocean community structure (Tara Oceans publication numbers 21, 22, 25, 41, 94, 128, 136). Genome-resolved and interactome-based approaches further showed that biotic interactions and functional specialization reinforce these large-scale patterns, linking biodiversity to ecosystem functioning across the global ocean (Tara Oceans publication number 120).
The Arctic Ocean emerged from Tara Oceans as a highly distinctive and internally structured ecosystem, rather than a simple extension of lower-latitude communities. Pan-Arctic analyses integrating metabarcoding, metagenomics, and environmental data revealed strong longitudinal and vertical structuring of plankton communities, shaped by sea-ice cover, freshwater inputs, and stratification (Tara Oceans publication number 144). Arctic plankton assemblages display unique taxonomic compositions, functional repertoires, and virus–host interaction networks, including distinct biogeographic patterns of giant viruses and microbial lineages adapted to extreme conditions (Tara Oceans publication numbers 94, 108, 122, 144, 147). Together, these studies position the Arctic as a singular marine biome, highly sensitive to climate-driven change and critical for understanding the future reorganization of ocean ecosystems.