Dramatic phenotypic plasticity in barnacle legs (Balanus glandula Darwin): magnitude, age dependence, and speed of response.

Limits to phenotypic plasticity: flow effects on barnacle feeding appendages.

Phenotypic plasticity, the capacity of a given genotype to produce differing morphologies in response to the environment, is widespread among marine organisms (1). For example, acorn barnacles feed by extending specialized appendages (the cirral legs) into flow, and the length of the cirri is plastic: the higher the velocity, the shorter the feeding legs (2,3). However, this effect has been exp...

Sources of invasions of a northeastern Pacific acorn barnacle, Balanus glandula, in Japan and Argentina

Within years of its introduction, the North American barnacle Balanus glandula Darwin, 1854 became an abundant member of rocky intertidal communities in Japan and Argentina. To determine the regional sources of these invasions, we compared mitochondrial cytochrome c oxidase subunit 1 (COI) and nuclear elongation factor 1 alpha (EF1) genotypes of native and introduced populations. Previously des...

Feeding in flow extremes: dependence of cirrus form on wave-exposure in four barnacle species.

Wave-exposure influences the form of many organisms. Curiously, the impact of flow extremes on feeding structures has received little attention. Barnacles extend feather-like legs to feed, and prior work revealed a highly precise association between leg length and water velocity in one species. To assess the generality of this flow-dependence, we quantified variation in four leg traits (ramus l...

The Affect of Low Tide on the Digestion of Balanus glandula, the Acorn Barnacle

Prolonged Withdrawal: A Possible Predator Evasion Behavior in Balanus glandula (Crustacea: Cirripedia)

The duration of cirral withdrawal in Balanus glandula (Darwin) varies by a factor of three depending on the type of stimulus applied. Contact with potential predators including thaidid gastropods (Thais emarginata, T. lamellosa), and forcipulate asteroids (Leptasterias hexactis, Pycnopodia helianthoides) elicits significantly longer withdrawal durations than contact with an herbivorous gastropo...