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Abstract Asymmetries in power (the ability to influence the outcome of conflict) are ubiquitous in social interactions because interacting individuals are rarely identical. It is well documented that asymmetries in power influence the outcome of reproductive conflict in social groups. Yet power asymmetries have received little attention in the context of negotiations between caring parents, which is surprising given that parents are often markedly different in size. Here we built on an existing negotiation model to examine how power and punishment influence negotiations over care. We incorporated power asymmetry by allowing the more-powerful parent, rank 1, to inflict punishment on the less-powerful parent, rank 2. We then determined when punishment will be favored by selection and how it would affect the negotiated behavioral response of each parent. We found that with power and punishment, a reduction in one parent’s effort results in partial compensation by the other parent. However, the degree of compensation is asymmetric: the rank 2 compensates more than the rank 1. As a result, the fitness of rank 1 increases and the fitness of rank 2 decreases, relative to the original negotiation model. Furthermore, because power and punishment enable one parent to extract greater effort from the other, offspring can do better, that is, receive more total effort, when there is power and punishment involved in negotiations over care. These results reveal how power and punishment alter the outcome of conflict between parents and affect offspring, providing insights into the evolutionary consequences of exerting power in negotiations. 

An ontogenetic analysis of the olfactory organ and the number and distribution of internal taste buds was carried out in two neon gobies (Elacatinus loriandElacatinus colini) with the goal of revealing morphological trends that might inform an understanding of the roles of olfaction and taste in larval orientation behaviour. The pattern of development of the olfactory organ is unremarkable and enclosure of the olfactory epithelium occurs concurrently with metamorphosis and settlement in both species. Like other gobies, juvenile and adultE. loriandE. colinilack complex olfactory lamellae, and lack the accessory nasal sacs present in some adult gobies that could facilitate active olfactory ventilation (i.e.,sniffing). A small number of internal taste buds are present at hatch with most found in the caudal region of the buccal cavity (on gill arches, roof of buccal cavity). As taste bud number increases, they demonstrate an anterior spread to the lips, buccal valves and tongue (i.e.,tissue covering the basihyal). In the absence of an active ventilatory mechanism for the olfactory organs, the water that moves through the buccal cavity with cyclic gill ventilation may provide chemical cues allowing the internal taste buds to play a role in chemical‐mediated orientation and reef‐seeking behavior in pelagic larval fishes.