Meeting Abstract

29.3  Friday, Jan. 4  Variation among families in cyprid response to surface wettability for the barnacle Amphibalanus amphitrite HOLM, E.R.; Naval Surface Warfare Center, West Bethesda, MD eric.holm@navy.mil

The attachment response of cypris larvae to surfaces of differing wettabilities varies among and within species of barnacles. I investigated whether variation in the wettability response within a population of the barnacle Amphibalanus amphitrite had a genetic basis. Five surfaces spanning a range of wettabilities were generated in borosilicate glass vials using silanes. Cyprids from 20 maternal families were assayed for attachment and metamorphosis in response to the surfaces, and to a positive control (settlement factor). The proportion of larvae permanently attaching to the surface served as the character of interest. Attachment in response to all the treatments varied significantly among the families. Family means of the proportion of larvae attaching to the treated surfaces were positively correlated within surface type (hydrophilic vs. hydrophobic), but uncorrelated across surface types. Attachment in response to the positive control was uncorrelated to response to any of the glass treatments, suggesting that variation in the response to surface wettability among families was not due to variation in larval vigor or timing of acquisition of metamorphic competence. As well, the pattern of correlations indicated that observed variation was likely unaffected by differences among families in age-related changes in attachment behavior. Instead, the results imply that response of barnacle cyprids to these surfaces is a product of genetic or maternal effects, and that these effects differ between hydrophilic and hydrophobic surfaces. This research was supported by funding from the Office of Naval Research.