Background The backbone of the eukaryotic tree of life contains taxa only found in molecular surveys, of which we still have a limited understanding. Such is the case of Picozoa, an enigmatic lineage of heterotrophic picoeukaryotes within the supergroup Archaeplastida, which has emerged as a significant component of marine microbial plank- tonic communities. To enhance our understanding of the diversity, distribution, and ecology of Picozoa, we conduct a comprehensive assessment at different levels, from assemblages to taxa, employing phylogenetic analysis, species distribution modeling, and ecological niche characterization. Results Picozoa was among the ten most abundant eukaryotic groups, found almost exclusively in marine environ- ments. The phylum was represented by 179 Picozoa’s OTU (pOTUs) placed in five phylogenetic clades. Picozoa com- munity structure had a clear latitudinal pattern, with polar assemblages tending to cluster separately from non-polar ones. Based on the abundance and occupancy pattern, the pOTUs were classified into four categories: Low-abundant, Widespread, Polar, and Non-polar. We calculated the ecological niche of each of these categories. Notably, pOTUs sharing similar ecological niches were not closely related species, indicating a phylogenetic overdispersion in Picozoa communities. This could be attributed to competitive exclusion and the strong influence of the seasonal amplitude of variations in environmental factors, such as temperature, shaping physiological and ecological traits. Conclusions Overall, this work advances our understanding of uncharted protists’ evolutionary dynamics and eco- logical strategies. Our results highlight the importance of understanding the species-level ecology of marine het- eroflagellates like Picozoa. The observed phylogenetic overdispersion challenges the concept of phylogenetic niche conservatism in protist communities, suggesting that closely related species do not necessarily share similar ecologi- cal niches.

Global distribution, diversity, and ecological niche of Picozoa, a widespread and enigmatic marine protist lineage / Huber, Paula; DE ANGELIS, Daniele; Sarmento, Hugo; Metz, Sebastian; Giner, Caterina R.; De Vargas, Colomban; Maiorano, Luigi; Massana, Ramon; Logares, Ramiro. - In: MICROBIOME. - ISSN 2049-2618. - 12:1(2024). [10.1186/s40168-024-01874-1]

Global distribution, diversity, and ecological niche of Picozoa, a widespread and enigmatic marine protist lineage

Daniele De Angelis;Luigi Maiorano;
2024

Abstract

Background The backbone of the eukaryotic tree of life contains taxa only found in molecular surveys, of which we still have a limited understanding. Such is the case of Picozoa, an enigmatic lineage of heterotrophic picoeukaryotes within the supergroup Archaeplastida, which has emerged as a significant component of marine microbial plank- tonic communities. To enhance our understanding of the diversity, distribution, and ecology of Picozoa, we conduct a comprehensive assessment at different levels, from assemblages to taxa, employing phylogenetic analysis, species distribution modeling, and ecological niche characterization. Results Picozoa was among the ten most abundant eukaryotic groups, found almost exclusively in marine environ- ments. The phylum was represented by 179 Picozoa’s OTU (pOTUs) placed in five phylogenetic clades. Picozoa com- munity structure had a clear latitudinal pattern, with polar assemblages tending to cluster separately from non-polar ones. Based on the abundance and occupancy pattern, the pOTUs were classified into four categories: Low-abundant, Widespread, Polar, and Non-polar. We calculated the ecological niche of each of these categories. Notably, pOTUs sharing similar ecological niches were not closely related species, indicating a phylogenetic overdispersion in Picozoa communities. This could be attributed to competitive exclusion and the strong influence of the seasonal amplitude of variations in environmental factors, such as temperature, shaping physiological and ecological traits. Conclusions Overall, this work advances our understanding of uncharted protists’ evolutionary dynamics and eco- logical strategies. Our results highlight the importance of understanding the species-level ecology of marine het- eroflagellates like Picozoa. The observed phylogenetic overdispersion challenges the concept of phylogenetic niche conservatism in protist communities, suggesting that closely related species do not necessarily share similar ecologi- cal niches.
2024
Picozoa, Protist, Marine picoeukaryotic, Heterotrophic flagellates, Molecular diversity, Species distribution modeling, Ecological niche, Phylogenetic overdispersion
01 Pubblicazione su rivista::01a Articolo in rivista
Global distribution, diversity, and ecological niche of Picozoa, a widespread and enigmatic marine protist lineage / Huber, Paula; DE ANGELIS, Daniele; Sarmento, Hugo; Metz, Sebastian; Giner, Caterina R.; De Vargas, Colomban; Maiorano, Luigi; Massana, Ramon; Logares, Ramiro. - In: MICROBIOME. - ISSN 2049-2618. - 12:1(2024). [10.1186/s40168-024-01874-1]
File allegati a questo prodotto
File Dimensione Formato  
Huber_Global_2024.pdf

accesso aperto

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Creative commons
Dimensione 8.04 MB
Formato Adobe PDF
8.04 MB Adobe PDF

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1720704
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 0
social impact