Barnacle structure formation

From the evolutionary point of view, structures or mechanisms that prove a success are likely to be passed on. However, adult barnacles probably do not control the structure formation process of their cement The ability of cypris larvae to sense physical and chemical surface properties most likely vanishes after attachment and metamorphosis, for the main function of the adult is to feed and to metabolize the energy into growth and reproduction. Instead, the above observations probably suggest that the structure formation process is simply a result of water uptake increasing the effective size of the adhesive filling spaces or gaps. 

Theoretical Colloid Approach to Structure Formation in Barnacle Adhesive... 

The process of structure formation of barnacle adhesive can be further discussed in the light of a biocoUoidal system The characteristics of biocolloids are based on the principle of self-organization [47]. 

It may be conceivable that the structure formation of barnacle adhesive is determined by critical self-assembly concentrations of the adhesive proteins within an interfacial gap between a barnacle base and a substrate. It can further be suggested that the biopolymers form coherent gel structures, in which two transitions of critical protein concentrations determine the arrangement of adhesive globules from a dense sheet-like formation to a slightly loose sponge-like formation to a very loose branched or web-like structure. 

The consideration outlined above agrees with the assumption that substrates influence the structure formation of barnacle adhesive indirectly via properties that hold the barnacle base at a distance from the surface (e.g., fiber coatings, thick biofilm layers) or cause large interfacial gaps (e.g., PDMS coatings). These factors affect the concentration in the dispersion, and hence the position on the adsorption isotherm as compared to the micellar or hemi-micellar concentration, by impinging on the interfacial volume that needs to be filled with adhesive. 

Knowledge of the structure of barnacle cement within colloidal dimensions has recently been gained. It is shown that the barnacle adhesive presents a useful tool for understanding and investigating formation of bioadhesive structures as colloidal systems. 

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