title: A case of modular phenotypic plasticity in the depth gradient for the gorgonian coral Antillogorgia bipinnata (Cnidaria: Octocorallia).
abstract: Phenotypic plasticity, as a phenotypic response induced by the environment, has been proposed as a key factor in the evolutionary history of corals. A significant number of octocoral species show high phenotypic variation, exhibiting a strong overlap in intra- and inter-specific morphologic variation. This is the case of the gorgonian octocoral Antillogorgia bipinnata (Verrill 1864), which shows three polyphyletic morphotypes along a bathymetric gradient. This research tested the phenotypic plasticity of modular traits in A. bipinnata with a reciprocal transplant experiment involving 256 explants from two morphotypes in two locations and at two depths. Vertical and horizontal length and number of new branches were compared 13 weeks following transplant. The data were analysed with a linear mixed-effects model and a graphic approach by reaction norms.
  
  
  
  At the end of the experiment, 91.8% of explants survived. Lower vertical and horizontal growth rates and lower branch promotion were found for deep environments compared to shallow environments. The overall variation behaved similarly to the performance of native transplants. In particular, promotion of new branches showed variance mainly due to a phenotypic plastic effect.
  
  
  
  Globally, environmental and genotypic effects explain the variation of the assessed traits. Survival rates besides plastic responses suggest an intermediate scenario between adaptive plasticity and local adaptation that may drive a potential process of adaptive divergence along depth cline in A. bipinnata.
authors.affiliation: Department of Animal Ecology and Systematics, Justus Liebig Universität, Heinrich-Buff-Ring 26-32 IFZ D-35392, Giessen, Germany. ifboti@gmail.com.|Laboratory of Biología Molecular Marina-Biommar, Department of Biological Sciences-Faculty of Sciences, Universidad de los Andes, Carrera 1E No 18A - 10, P.O. Box 4976, Bogotá, Colombia. ifboti@gmail.com.
authors.forename: Iván
authors.initials: I
authors.lastname: Calixto-Botía
authors.affiliation: Laboratory of Biología Molecular Marina-Biommar, Department of Biological Sciences-Faculty of Sciences, Universidad de los Andes, Carrera 1E No 18A - 10, P.O. Box 4976, Bogotá, Colombia.|Marine Sciences, International Giessen Graduate Centre for the Life Sciences (GGL), Justus Liebig Universität, Giessen, Germany.
authors.forename: Juan A
authors.initials: JA
authors.lastname: Sánchez
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D037421:Anthozoa / Q000502:physiology; D005075:Biological Evolution; D004777:Environment; D005838:Genotype; D010641:Phenotype
keywords: Antillogorgia bipinnata; Depth cline; Octocoral; Phenotypic plasticity; Reaction norm