DOI: 10.5061/dryad.w0vt4b8pg
title: Size-selective mortality induces evolutionary changes in group risk-taking behavior and the circadian system in a fish

description: 1. Intensive and trait-selective mortality of fish and wildlife can cause
 evolutionary changes in a range of life-history and behavioral traits.
 These changes might in turn alter the circadian system due to
 coevolutionary mechanisms or correlated selection responses both at
 behavioral and molecular levels, with knock-on effects on daily
 physiological processes and behavioral outputs. 2. We examined the
 evolutionary impact of size-selective harvesting on group risk-taking
 behavior and the circadian system in a model fish species. We exposed
 zebrafish (Danio rerio) to either large or small size-selective harvesting
 relative to a control over five generations, followed by eight generations
 during which harvesting halted to remove maternal effects. 3.
 Size-selective mortality affected fine-scale timing of behaviors. In
 particular, small size-selective mortality, typical of specialized
 fisheries and gape-limited predators targeting smaller size classes,
 increased group risk-taking behavior during feeding and after simulated
 predator attacks. Moreover, small size-selective mortality increased early
 peaks of daily activity as well as extended self-feeding daily activity to
 the photophase compared to controls. By contrast large size-selective
 mortality, typical of most wild capture fisheries, only showed an almost
 significant effect of decreasing group risk-taking behavior during the
 habituation phase and no clear changes in fine-scale timing of daily
 behavioral rhythms compared to controls. 4. We also found changes in the
 molecular circadian core clockwork in response to both size selective
 mortality treatments. These changes disappeared in the clock output
 pathway because both size-selected lines showed similar transcription
 profiles. This switch downstream to the molecular circadian core clockwork
 also resulted in similar overall behavioral rhythms (diurnal swimming and
 self-feeding in the last hours of darkness) independent of the underlying
 molecular clock. 5. To conclude, our experimental harvest left an
 asymmetrical evolutionary legacy in group risk-taking behavior and in
 fine-scale daily behavioral rhythms. Yet, the overall timing of activity
 showed evolutionary resistance probably maintained by a molecular switch.
 Our experimental findings suggest that size-selective mortality can have
 consequences for behavior and physiological processes.
description: This dataset contains several data related to Zebrafish
 (<em>Danio rerio</em>): - behavioral data
 regarding risk-taking behavior (i.e., time spent at the surface of the
 water as recorded by automated video image tracking). -
 behavioral data regarding activity rhythms recorded using infrared
 sensors - gene expression - Standard
 lenght of fish   The
 dataset is organized in an excel file with the following sheets:
 1) diving_test - Line: the selection
 line - Rep: the replicate of each selection
 line - Group: the group which is the experimental
 unit - Trial: the different trials -
 Time: Time within each trial (30-s bins) - Surf_time:
 Cumulative time spent at the surface 2)
 activity_rhythms - PHENOTYPE: swimming or self
 feeding - PHASE: first or second light-dark
 phase - TIME: time within each 24-h light-dark phase
 (10 min bin) - LIGHT: 0 = dark; 1 = light
 - LINE: the selection line - ACT: total
 activity - se.up: standard error up
 - se.down: standard error down 3)
 mesor_noct - PHENOTYPE: swimming or self
 feeding - LINE: the selection line -
 LINE.REP: the replicate of each selection line - GROUP:
 the group which is the experimental unit - PHASE: first
 or second light-dark phase - MESOR: the midline
 estimating statistic of rhythm - Area: area under the
 waveform curve, AUC - E_At: early daily activity
 (percentage of activity during the first four hours of light)
 4) feeding - LINE: the selection
 line - LINE.REP: the replicate of each selection
 line - GROUP: the group which is the experimental
 unit - PHASE: first or second light-dark
 phase - TIME: from to two hours before light-on (1) to
 one hour after light-on (4), including cumulative level (ALL)
 - A: area under the waveform curve, AUC 
 5) input_R_circadian - LINE: the selection
 line - REP: the replicate of each selection
 line - TISSUE: B = brain; L = liver
 - TIME: sampling time (24 h) - From column E
 to column Q: RTqPCR readings 6)
 standard_length - DPF: days post
 fertilization - LINE: the selection line
 - REP: the replicate of each selection line -
 GROUP: the group which is the experimental unit SL.cm:
 individual standard length within the group
description: There are some missing values due to experimental problems.