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Relationship: 1032


A descriptive phrase which clearly defines the two KEs being considered and the sequential relationship between them (i.e., which is upstream, and which is downstream). More help

Reduced, Anterior swim bladder inflation leads to Reduced, Hearing

Upstream event
The causing Key Event (KE) in a Key Event Relationship (KER). More help
Downstream event
The responding Key Event (KE) in a Key Event Relationship (KER). More help

Key Event Relationship Overview

The utility of AOPs for regulatory application is defined, to a large extent, by the confidence and precision with which they facilitate extrapolation of data measured at low levels of biological organisation to predicted outcomes at higher levels of organisation and the extent to which they can link biological effect measurements to their specific causes.Within the AOP framework, the predictive relationships that facilitate extrapolation are represented by the KERs. Consequently, the overall WoE for an AOP is a reflection in part, of the level of confidence in the underlying series of KERs it encompasses. Therefore, describing the KERs in an AOP involves assembling and organising the types of information and evidence that defines the scientific basis for inferring the probable change in, or state of, a downstream KE from the known or measured state of an upstream KE. More help

AOPs Referencing Relationship

Taxonomic Applicability

Latin or common names of a species or broader taxonomic grouping (e.g., class, order, family) that help to define the biological applicability domain of the KER.In general, this will be dictated by the more restrictive of the two KEs being linked together by the KER.  More help
Term Scientific Term Evidence Link
zebrafish Danio rerio NCBI
fathead minnow Pimephales promelas NCBI

Sex Applicability

An indication of the the relevant sex for this KER. More help

Life Stage Applicability

An indication of the the relevant life stage(s) for this KER.  More help

Key Event Relationship Description

Provides a concise overview of the information given below as well as addressing details that aren’t inherent in the description of the KEs themselves. More help

Apart from a role in buoyancy that is not completely understood with regard to the relation to the function of the posterior chamber, the anterior chamber of the swim bladder of many fish species has an additional role in the production and/or detection of sound (Popper et al., 1974; Bang et al., 2002). Several fish families have Weberian ossicles (tiny bones, also called the Weberian apparatus), connecting the anterior chamber to the inner ear resulting in an amplification of sound waves. Therefore it is plausible to assume that if the anterior chamber does not inflate or inflates to a reduced size, the connection to the Weberian ossicles is lost and hearing is impaired.

Evidence Collection Strategy

Include a description of the approach for identification and assembly of the evidence base for the KER. For evidence identification, include, for example, a description of the sources and dates of information consulted including expert knowledge, databases searched and associated search terms/strings.  Include also a description of study screening criteria and methodology, study quality assessment considerations, the data extraction strategy and links to any repositories/databases of relevant references.Tabular summaries and links to relevant supporting documentation are encouraged, wherever possible. More help

Evidence Supporting this KER

Addresses the scientific evidence supporting KERs in an AOP setting the stage for overall assessment of the AOP. More help
Biological Plausibility
Addresses the biological rationale for a connection between KEupstream and KEdownstream.  This field can also incorporate additional mechanistic details that help inform the relationship between KEs, this is useful when it is not practical/pragmatic to represent these details as separate KEs due to the difficulty or relative infrequency with which it is likely to be measured.   More help

It is plausible to assume that if the anterior chamber does not inflate or inflates to a reduced size, the connection to the Weberian ossicles is lost and hearing is impaired.

Uncertainties and Inconsistencies
Addresses inconsistencies or uncertainties in the relationship including the identification of experimental details that may explain apparent deviations from the expected patterns of concordance. More help

Known modulating factors

This table captures specific information on the MF, its properties, how it affects the KER and respective references.1.) What is the modulating factor? Name the factor for which solid evidence exists that it influences this KER. Examples: age, sex, genotype, diet 2.) Details of this modulating factor. Specify which features of this MF are relevant for this KER. Examples: a specific age range or a specific biological age (defined by...); a specific gene mutation or variant, a specific nutrient (deficit or surplus); a sex-specific homone; a certain threshold value (e.g. serum levels of a chemical above...) 3.) Description of how this modulating factor affects this KER. Describe the provable modification of the KER (also quantitatively, if known). Examples: increase or decrease of the magnitude of effect (by a factor of...); change of the time-course of the effect (onset delay by...); alteration of the probability of the effect; increase or decrease of the sensitivity of the downstream effect (by a factor of...) 4.) Provision of supporting scientific evidence for an effect of this MF on this KER. Give a list of references.  More help
Response-response Relationship
Provides sources of data that define the response-response relationships between the KEs.  More help
Information regarding the approximate time-scale of the changes in KEdownstream relative to changes in KEupstream (i.e., do effects on KEdownstream lag those on KEupstream by seconds, minutes, hours, or days?). More help
Known Feedforward/Feedback loops influencing this KER
Define whether there are known positive or negative feedback mechanisms involved and what is understood about their time-course and homeostatic limits. More help

Domain of Applicability

A free-text section of the KER description that the developers can use to explain their rationale for the taxonomic, life stage, or sex applicability structured terms. More help

Within fish we can distinguish between hearing generalists (non-specialists) such as cichlids, salmonids, sunfishes and toadfishes and hearing specialists which have accessory hearing structures (specializations) such as the Weberian apparatus in otophysines, supbrabranchial chambers in labyrinth fish and auditory bullae in mormyrids (Ladich and Wysocki, 2003; Ladich and Fay, 2013). In fish that do not possess an anterior chamber with a function in hearing this KER is not applicable.


List of the literature that was cited for this KER description. More help

Bang, P.I., Yelick, P.C., Malicki, J.J., Sewell, W.F., 2002. High-throughput behavioral screening method for detecting auditory response defects in zebrafish. Journal of Neuroscience Methods 118, 177-187.

Ladich, F., Fay, R.R., 2013. Auditory evoked potential audiometry in fish. Reviews in Fish Biology and Fisheries 23, 317-364.

Ladich, F., Wysocki, L.E., 2003. How does tripus extirpation affect auditory sensitivity in goldfish? Hearing Research 182, 119-129.

Lechner, W., Ladich, F., 2008. Size matters: Diversity in swimbladders and Weberian ossicles affects hearing in catfishes. Journal of Experimental Biology 211, 1681-1689.

Popper, A.N., 1974. Response of swim bladder of goldfish (Carassius auratus) to acoustic stimuli. Journal of Experimental Biology 60, 295-304.

Yan, H.Y., Fine, M.L., Horn, N.S., Colon, W.E., 2000. Variability in the role of the gasbladder in fish audition. Journal of Comparative Physiology a-Sensory Neural and Behavioral Physiology 186, 435-445.