title: Biomineralization changes with food supply confer juvenile scallops (Argopecten purpuratus) resistance to ocean acidification.
abstract: Future ocean acidification (OA) will affect physiological traits of marine species, with calcifying species being particularly vulnerable. As OA entails high energy demands, particularly during the rapid juvenile growth phase, food supply may play a key role in the response of marine organisms to OA. We experimentally evaluated the role of food supply in modulating physiological responses and biomineralization processes in juveniles of the Chilean scallop, Argopecten purpuratus, that were exposed to control (pH ~ 8.0) and low pH (pH ~ 7.6) conditions using three food supply treatments (high, intermediate, and low). We found that pH and food levels had additive effects on the physiological response of the juvenile scallops. Metabolic rates, shell growth, net calcification, and ingestion rates increased significantly at low pH conditions, independent of food. These physiological responses increased significantly in organisms exposed to intermediate and high levels of food supply. Hence, food supply seems to play a major role modulating organismal response by providing the energetic means to bolster the physiological response of OA stress. On the contrary, the relative expression of chitin synthase, a functional molecule for biomineralization, increased significantly in scallops exposed to low food supply and low pH, which resulted in a thicker periostracum enriched with chitin polysaccharides. Under reduced food and low pH conditions, the adaptive organismal response was to trade-off growth for the expression of biomineralization molecules and altering of the organic composition of shell periostracum, suggesting that the future performance of these calcifiers will depend on the trajectories of both OA and food supply. Thus, incorporating a suite of traits and multiple stressors in future studies of the adaptive organismal response may provide key insights on OA impacts on marine calcifiers.
authors.affiliation: Global Change Department, Instituto Mediterráneo de Estudios Avanzados (CSIC-UIB), C/ Miquel Marqués 21, 07190, Esporles, Islas Baleares, Spain.|Centro de Investigación e Innovación para el Cambio Climático (CiiCC), Universidad Santo Tomás, Ejercito 146, Santiago, Chile.
authors.forename: Laura
authors.initials: L
authors.lastname: Ramajo
authors.affiliation: Global Change Department, Instituto Mediterráneo de Estudios Avanzados (CSIC-UIB), C/ Miquel Marqués 21, 07190, Esporles, Islas Baleares, Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Marbà
authors.affiliation: Centro de Investigación e Innovación para el Cambio Climático (CiiCC), Universidad Santo Tomás, Ejercito 146, Santiago, Chile.
authors.forename: Luis
authors.initials: L
authors.lastname: Prado
authors.affiliation: Université Pierre et Marie Curie, 4 Place Jussieu, 75005, Paris, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Peron
authors.affiliation: Facultad de Artes Liberales and Ingeniería y Ciencias, Universidad Adolfo Ibañez, Avenida Diagonal Las Torres 2640, 7941169, Peñalolen, Santiago, Chile.|Center for the Study of Multiple-drivers on Marine Socio-Ecological Systems (MUSELS), Universidad de Concepción, 4030000 Concepción, Chile.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Lardies
authors.affiliation: Departamento de Mineralogía y Petrología, Universidad de Granada, Avenida Fuentenueva, 18071 Granada, Spain.
authors.forename: Alejandro B
authors.initials: AB
authors.lastname: Rodriguez-Navarro
authors.affiliation: Center for the Study of Multiple-drivers on Marine Socio-Ecological Systems (MUSELS), Universidad de Concepción, 4030000 Concepción, Chile.|Laboratorio de Funcionamiento de Ecosistema Acuáticos (LAFE), Departamento de Sistemas Acuáticos, Facultad de Ciencias Ambientales, Universidad de Concepción, 4030000 Concepción, Chile.
authors.forename: Cristian A
authors.initials: CA
authors.lastname: Vargas
authors.affiliation: Centro de Investigación e Innovación para el Cambio Climático (CiiCC), Universidad Santo Tomás, Ejercito 146, Santiago, Chile.|Center for the Study of Multiple-drivers on Marine Socio-Ecological Systems (MUSELS), Universidad de Concepción, 4030000 Concepción, Chile.
authors.forename: Nelson A
authors.initials: NA
authors.lastname: Lagos
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Thuwal, 23955-6900, Saudi Arabia.
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Duarte
mesh_terms: D000222:Adaptation, Physiological; D060105:Animal Shells / Q000502:physiology*; D000818:Animals; D002113:Calcification, Physiologic; D002677:Chile; D002686:Chitin / Q000737:chemistry; D002687:Chitin Synthase / Q000737:chemistry; D057231:Climate Change; D020387:Food Chain; D006863:Hydrogen-Ion Concentration; D009792:Oceans and Seas; D010101:Oxygen Consumption; D049897:Pectinidae / Q000502:physiology*; D012623:Seawater / Q000737:chemistry*
chemical_list: D002686:Chitin; D002687:Chitin Synthase
keywords: food; natural variability; ocean acidification; periostracum; protein expression; resistance; tolerance