About the project

MarSymbiOmics is a multi-disciplinary project, led by the Centre d’Estudis Avançats de Blanes (CEAB-CSIC), which involves scientists from several countries. It has been funded by the Spanish Ministry of Economy and Competitiveness (MINECO), “I+D Projects of Excellence call- 2013, and will run since January First 2014 till December 31, 2017.

Symbioses represent a basic but often cryptic contribution to the diversity and stability of marine ecosystems, allowing the symbiotic partners to extent their ecological range and even colonize extreme habitats that would be inaccessible for the single organisms alone.  Sponges appear to be an ideal model to study marine symbiosis from both evolutionary and ecological perspectives. They are the oldest extant metazoans, as well as a paradigm for the diversity and abundance of associated partners, and have been reported to harbor associated symbionts (i.e. microbes) since the Pre-Cambrian.

The project focuses on marine sponges and is build around the hypotheses that sponge microbiomes i) are at the base of some metazoan traits ii) are key in maintaining biodiversity and function in benthic ecosystems iii) may be modulated by associated invertebrates such as polychaetes, and iv) are particularly vulnerable to environmental changes.

The sponges targeted in the project will encompass species with intracellular bacteria from both tropical and temperate benthic ecosystems, and extracellular bacteria and polychaetes from tropical ecosystems.



By using descriptive and experimental approaches and metagenomics and metatranscriptomics technologies, MarSymbiOmics pursues the following key objectives:

  • To discover the extent and patterns of hidden biodiversity in sponge models and their temporal, ontogenetic, and geographic variability.
  • To identify genes and expression profiles involved in the symbiosis establishment and functioning.
  • To address the contribution of the symbiotic life style to the holobiont success (costs/benefits).
  • To assess whether macrosymbionts (i.e. polychaetes) may modulate microbial symbioses in sponges harboring both types of organisms.
  • To analyze symbiosis vulnerability in temperate ecosystems facing ocean changes.
  • To predict the ecological repercussions of symbiosis disruption in benthic systems.
  • To disseminate the main results of the project to the general public, ecologists, administrations, and scientists from other disciplines.
Hemimycale columella

Hemimycale columella 

Petrosia ficiformis

Ircinia fasciculata

Indopacific symbiotic polychaetes

Dividing calcibacteria entrapped within the calcareous coat

sponge symbiosis