Population structure of the Spanish sardine Sardinella aurita : natural morphological variation in a genetically homogeneous population

摘要: The population structure of the Spanish sardine Sardirella aurita in coastal waters Florida, USA, was examined using protein electrophoresis (one sample from Charleston, South Carolina, analyzed as a geographic outlier), morphometrics, and meristics. Electrophoresis proteins coded by 37 presumed genetic loci revealed low levels variation, little allele frequency variation among samples, distances between samples. Gene flow high effectively homogenized locations, indicating that single, panmictic sardines exists at least Carolina to Florida panhandle. Size-corrected principal-components analyses performed on morphometric data (collected form truss network) regional allometric patterns. These patterns were most apparent small fish less obvious larger fish, implying morphological may diminish grow. Regressions gill-raker number fork length demonstrated similar those seen analyses. absence evidence for populational structuring ontogenetic plasticity body shape suggests be ecophenotypic. Alternatively, electrophoretic not have detected substructuring exists. Both meristic tended group samples collected embayments separately more oceanic environments, proximity influence some observed variation. It appears sardines, other clupeids, is useful determining evolutionary structuring, are merit studying short-term, environmentally induced