Year: 2026
Type: preprint
Abstract: A major unsolved question in ecology and evolution is how similar free-living and symbiotic microbial communities are. In marine systems, depth homogenises free-living communities due to stronger dispersal and weaker environmental filtering compared to surface waters. We show that symbiotic communities of marine sponges follow a different pattern, with a subset of sponge species mirroring the increased similarity with depth seen in their free-living counterparts, while others remain highly host-specific both in shallow and deep waters. Moreover, in deep waters, more phylogenetically similar hosts harbor more similar microbiomes, yet host-symbiont cophylogeny nearly vanishes. This reveals two contrasting eco-evolutionary assembly rules: in more constant environments like the deep sea, community assembly is driven by host and environmental filtering with minimal signature of coevolution, whereas in variable environments, like shallow waters, host-symbiont coevolution is strong and key to maintain host-specific microbiomes.
Language: English
Subfield: Biotechnology
Domain: Life Sciences
SDG: Life below water
Open Access status: green
Awards: G39567056, G3960473525, G7658697405
OpenAlex ID: W7223307987