In species in which intense intermale competition for the access to females is present males of lower competitive ability may adopt alternative reproductive tactics (ART) to get access to mates. These ART translate in many cases into male sexual polymorphism, with individuals following distinctly different tactics. Usually two alternative male morphs can be recognized in species with ART: (1) bourgeois males that compete for access to mates invest in typically male behaviors, such as building elaborated nests or displaying ornaments; and (2) parasitic males that take advantage of the success of the bourgeois males in attracting females and attempt "sneaker" fertilizations (e.g., sneaker and satellite males). In combtooth blennies (Blenniidae) the co-occurrence of ART and male sexual polymorphism has been described for two temperate species: the peacock blenny, Salaria pavo, and the Azorean rock-pool blenny, Parablennius sanguinolentus parvicornis. Interestingly, while in the peacock blenny the alternative male morph adopts a sneaker tactic, in the rock-pool blenny parasitic males act as satellites to nest-holder males. Thus, this variation in the ART expressed in these two closely related species allows for a comparative study of the proximate and ultimate factors affecting the expression of the two ART. In this article we summarize the available information on @entity342 levels in bourgeois and parasitic males of natural populations of the two species and of recent studies on the effect of exogenous administration of @entity3800 on tactic switching in parasitic males of the two species. The information is discussed within the frame of the relative @entity545 , which predicts that plastic alternative morphs should show differences in hormone levels and that the administration of sex @entity230 should be effective in promoting the switch from the parasitic to bourgeois tactic. The evidence is only partly consistent with this hypothesis. Alternatively, a social transduction hypothesis that better fits the available data on @entity3800 and ART in teleost is proposed. It states that the observed differences in @entity342 levels between alternative morphs should not be interpreted as an organization vs activation effect of @entity230 , but rather as the limited vs lifelong responsiveness of the @entity8799 to social regulation.

Male sexual polymorphism, alternative reproductive tactics, and XXXX in combtooth blennies (pisces: blenniidae).

@entity8799 :: ('MESH:D018358', 'Disease') :: ['neuroendocrine axis'] @entity545 :: ('MESH:D010411', 'Disease') :: ['plasticity hypothesis'] @entity342 :: ('CHEBI:50113', 'Chemical') :: ['androgen'] @entity230 :: ('MESH:D013256', 'Chemical') :: ['steroids'] @entity3800 :: ('MESH:D000728', 'Chemical') :: ['androgens']
@entity3800 :: (MESH:D000728,Chemical) :: ['androgens']
