Loading...
Research Project
Comparative social cognition: zebrafish as a neurobehavioural model
Funder
Authors
Publications
Brain transcriptomic response to social eavesdropping in zebrafish (Danio rerio)
Publication . Lopes, Joao Sollari; Abril-de-Abreu, Rodrigo; Oliveira, Rui Filipe
Public information is widely available at low cost to animals living in social groups. For
instance, bystanders may eavesdrop on signaling interactions between conspecifics and use
it to adapt their subsequent behavior towards the observed individuals. This social eavesdropping
ability is expected to require specialized mechanisms such as social attention,
which selects social information available for learning. To begin exploring the genetic basis of
social eavesdropping, we used a previously established attention paradigm in the lab to study
the brain gene expression profile of male zebrafish (Danio rerio) in relation to the attention
they paid towards conspecifics involved or not involved in agonistic interactions. Microarray
gene chips were used to characterize their brain transcriptomes based on differential expression
of single genes and gene sets. These analyses were complemented by promoter regionbased
techniques. Using data from both approaches, we further drafted protein interaction
networks. Our results suggest that attentiveness towards conspecifics, whether interacting or
not, activates pathways linked to neuronal plasticity and memory formation. The network
analyses suggested that fos and jun are key players on this response, and that npas4a, nr4a1
and egr4 may also play an important role. Furthermore, specifically observing fighting interactions
further triggered pathways associated to a change in the alertness status (dnajb5) and
to other genes related to memory formation (btg2, npas4b), which suggests that the acquisition
of eavesdropped information about social relationships activates specific processes on
top of those already activated just by observing conspecifics.
Social dominance modulates eavesdropping in zebrafish
Publication . Abril-de-Abreu, Rodrigo; Cruz, Ana S.; Oliveira, Rui Filipe
Group living animals may eavesdrop on signalling interactions between conspecifics and integrate it with their own past social experience in order to optimize the use of relevant information from others. However, little is known about this interplay between public (eavesdropped) and private social information. To investigate it, we first manipulated the dominance status of bystander zebrafish. Next, we either allowed or prevented bystanders from observing a fight. Finally, we assessed their behaviour towards the winners and losers of the interaction, using a custom-made video-tracking system and directional analysis. We found that only dominant bystanders who had seen the fight revealed a significant increase in directional focus (a measure of attention) towards the losers of the fights. Furthermore, our results indicate that information about the fighters' acquired status was collected from the signalling interaction itself and not from post-interaction status cues, which implies the existence of individual recognition in zebrafish. Thus, we show for the first time that zebrafish, a highly social model organism, eavesdrop on conspecific agonistic interactions and that this process is modulated by the eavesdroppers' dominance status. We suggest that this type of integration of public and private information may be ubiquitous in social learning processes.
Social eavesdropping in zebrafish: Tuning of attention to social interactions
Publication . Abril-de-Abreu, Rodrigo; Cruz, José; Oliveira, Rui Filipe
Group living animals may eavesdrop on signalling interactions between conspecifics in order to
collect adaptively relevant information obtained from others, without incurring in the costs of firsthand
information acquisition. This ability (aka social eavesdropping) is expected to impact Darwinian
fitness, and hence predicts the evolution of cognitive processes that enable social animals to use
public information available in the environment. These adaptive specializations in cognition may have
evolved both at the level of learning and memory mechanisms, and at the level of input mechanisms,
such as attention, which select the information that is available for learning. Here we used zebrafish
to test if attention in a social species is tuned to the exchange of information between conspecifics.
Our results show that zebrafish are more attentive towards interacting (i.e. fighting) than towards
non-interacting pairs of conspecifics, with the exposure to fighting not increasing activity or stress
levels. Moreover, using video playbacks to manipulate form features of the fighting fish, we show
that during the assessment phase of the fight, bystanders’ attention is more driven by form features
of the interacting opponents; whereas during the post-resolution phase, it is driven by biological
movement features of the dominant fish chasing the subordinate fish.
Social competence: an evolutionary approach
Publication . Taborsky, Barbara; Oliveira, Rui Filipe
'Social competence' refers to the ability of an individual to optimise its social behaviour depending on available social information. Although such ability will enhance social interactions and thus raise Darwinian fitness, its evolutionary and ecological significance has been largely ignored. Social competence is based on behavioural flexibility. We propose that the study of social competence requires an integrative approach that aims to understand how the brain translates social information into flexible behavioural responses, how flexibility might be constrained by the developmental history of an individual or by trade-offs with other (ecological) competences, and how social plasticity feeds back on fitness. Finally we propose a hypothesis of how social competence can become a driver of social evolution.
Audience effects and aggressive priming in agonistic behaviour of male zebrafish, Danio rerio
Publication . Cruz, Ana S.; Oliveira, Rui Filipe
Animals communicate through the exchange of signals. However, third-party individuals can detect and
intercept signals not directly sent to them, a phenomenon known as eavesdropping, and the presence of
bystanders can influence the signalling behaviour of interacting conspecifics, a phenomenon named the
audience effect. So far, research done on audience effects and eavesdropping has been mainly focused on
their function, rather than on their proximate mechanisms. For this reason, we were interested in testing
the occurrence of audience effects on male zebrafish, a genetically tractable model organism that is
emerging as a major candidate for the study of the neural basis of social behaviour. Here, pairs of males
were exposed to a mixed-sex shoal, which was used as an audience, at two different times: (1) during a
contest between them, to test for an audience effect and (2) before the contest, to test whether this prior
exposure influences subsequent agonistic behaviour (i.e. aggressive priming). We analysed the pairs'
aggressive signalling during the contest by measuring variables that characterize both the individuals'
behaviour and the interaction, and found that pre-exposure to an audience induced a shorter latency to
display, an increase in the time dominants spent chasing subordinates and a shorter time to resolve the
agonistic interaction. Also, exposure to the audience during the interaction led to a higher number of
interactions in which displays occurred, a higher number of resolved interactions with displays and a
decrease in the escalation of aggression for resolved interactions. These results add zebrafish to the
literature on the audience effect and, most importantly, open the way for the study of the neural
mechanisms involved in the processing of social information in a model organism.
Organizational Units
Description
Keywords
Contributors
Funders
Funding agency
Fundação para a Ciência e a Tecnologia
Funding programme
3599-PPCDT
Funding Award Number
PTDC/PSI-PCO/118776/2010