Dataset Information

Relative weighting of acoustic information during mating decisions in grasshoppers indicates signatures of sexual selection.

ABSTRACT: The decision with whom to mate is crucial in determining an individual's fitness and is often based on the evaluation of visual or acoustic displays produced during courtship. Accordingly, the algorithms for evaluating such courtship signals are shaped by sexual selection and should reflect the expected benefits and costs of mating: signals bearing heterospecific features should be rapidly rejected, since mating would produce no fertile offspring, while signals resembling conspecific ones should be weighted proportional to mate quality. We test these hypotheses in females of the grasshopper Chorthippus biguttulus who assess males by their song, which is produced as a sequence of subunits with species and individual specific signatures. We present mixed sequences of subunits with conflicting cues and use a computational model of decision-making to infer how sensory information is weighted and integrated over the song. Consistent with our hypothesis, females do weight sensory cues according to the expected fitness benefits/costs: heterospecific subunits are weighted particularly negatively and lead to a rejection of the male early in the song. Conspecific subunits are weighted moderately, permitting a more complete evaluation of the full song. However, there exists an overall negative bias against mating, possible causes of which are discussed.

SUBMITTER: Clemens J

PROVIDER: S-EPMC5644699 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Relative weighting of acoustic information during mating decisions in grasshoppers indicates signatures of sexual selection.

Clemens Jan J Aufderheide Jennifer J Ronacher Bernhard B

Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology 20170721 11

The decision with whom to mate is crucial in determining an individual's fitness and is often based on the evaluation of visual or acoustic displays produced during courtship. Accordingly, the algorithms for evaluating such courtship signals are shaped by sexual selection and should reflect the expected benefits and costs of mating: signals bearing heterospecific features should be rapidly rejected, since mating would produce no fertile offspring, while signals resembling conspecific ones should ...[more]

PMID: 28733816

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Project description:When reaching to an object, information about the target location as well as the initial hand position is required to program the motor plan for the arm. The initial hand position can be determined by proprioceptive information as well as visual information, if available. Bayes-optimal integration posits that we utilize all information available, with greater weighting on the sense that is more reliable, thus generally weighting visual information more than the usually less reliable proprioceptive information. The criterion by which information is weighted has not been explicitly investigated; it has been assumed that the weights are based on task- and effector-dependent sensory reliability requiring an explicit neuronal representation of variability. However, the weights could also be determined implicitly through learned modality-specific integration weights and not on effector-dependent reliability. While the former hypothesis predicts different proprioceptive weights for left and right hands, e.g., due to different reliabilities of dominant vs. nondominant hand proprioception, we would expect the same integration weights if the latter hypothesis was true. We found that the proprioceptive weights for the left and right hands were extremely consistent regardless of differences in sensory variability for the two hands as measured in two separate complementary tasks. Thus we propose that proprioceptive weights during reaching are learned across both hands, with high interindividual range but independent of each hand's specific proprioceptive variability. NEW & NOTEWORTHY How visual and proprioceptive information about the hand are integrated to plan a reaching movement is still debated. The goal of this study was to clarify how the weights assigned to vision and proprioception during multisensory integration are determined. We found evidence that the integration weights are modality specific rather than based on the sensory reliabilities of the effectors.

Dataset Information

Relative weighting of acoustic information during mating decisions in grasshoppers indicates signatures of sexual selection.

Publications

Relative weighting of acoustic information during mating decisions in grasshoppers indicates signatures of sexual selection.

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