Beyond abundance: ecological and functional relevance of intestinal fungi in the fish gut microbiome.

Intestinal fungi in fish gut microbiomes are recurrent, ecologically active, and influence host outcomes despite low read fractions, challenging traditional abundance-based views.

• Why it matters: Understanding the role of fungi is crucial because current research underestimates their ecological and functional importance, which may impact host health and microbiome models.
• What they did: The study reviews evidence from fish systems showing fungi's recurrent presence, their assembly influenced by host and environment, and their roles through enzymatic activity, immune modulation, and ecological interactions, despite low sequencing reads.
• The result: Incorporating fungi into fish gut microbiome models emphasizes ecological filtering and functional roles over abundance, enabling a more accurate understanding of their contributions to host health and microbiome dynamics.