DOI: 10.5061/dryad.00000005n
title: Personality, sperm traits and a test for their combined dependence on male condition in guppies

description: There is evidence that animal personality traits can have spill-over
 effects for sexual selection, with studies reporting that male behavioural
 types are associated with success during pre- and post-copulatory sexual
 selection. Given these links between personality and sexual traits, and
 the evidence that their expression can depend on an individual’s
 nutritional status (i.e. condition), a novel prediction is that changes in
 a male’s diet should alter both the average expression of personality and
 sexual traits, and their covariance. We tested these predictions using the
 guppy Poecilia reticulata, a species previously shown to exhibit strong
 condition dependence in ejaculate traits and a positive correlation
 between sperm production and individual variation in boldness. Contrary to
 expectation, we found that dietary restriction – when administered in
 mature adult males – did not affect the expression of either behavioural
 (boldness and activity) or ejaculate traits, although we did find that
 males subjected to dietary stress exhibited a positive association between
 sperm velocity and boldness that was not apparent in the unrestricted diet
 group. This latter finding points to possible context-dependent patterns
 of covariance between sexually selected and personality traits, which may
 have implications for patterns of selection and evolutionary processes
 under fluctuating environmental conditions.
description: This dataset contains measures for two behavioural traits
 (boldness and activity) and two ejaculate traits (sperm number and sperm
 velocity)  from male guppies that had been fed either high diet quantity
 (1.9mg per day) or low diet quantity (0.9 mg per day) for one month prior
 to trials. During feeding trials, opaque screens were placed between
 adjacent individual male tanks to avoid behavioural interactions between
 test subjects. To ensure that the males were stimulated to produce sperm
 throughout the course of the study, female guppies were placed within view
 of each tank, as male guppies remain sexually active in the presence of
 females  Males were tested for behavioural traits at
 the end of the diet treatments, acorss two repeated measures assays (with
 one day recovery in between). Each fish was placed initially inside an
 uncovered circular refuge of opaque PVC (, which itself was placed within
 a circular arena  A video camera was secured above the arena to allow the
 fish’s movements to be observed without human disturbance. After a
 5-minute period, during which the fish was allowed to acclimatize to its
 new surroundings, the door of the refuge was gently pulled away, allowing
 the fish to emerge. Using video footage, the time (in seconds) taken by an
 individual to emerge from the refuge was recorded. If the individual
 emerged within 10 minutes, its behaviour while moving around the arena was
 then observed over an additional 5-minute interval. The time (in seconds)
 the individual spent inactive or ‘frozen,’ as opposed to actively moving
 around, was measured over this period. The data for emergence time and
 time spent frozen were then inverted to provide final scores for
 ‘boldness’ and ‘activity’, respectively. Ejaculates
 were extracted under anaesthesia after the last behavioural trial. Sperm
 velcoity (VCL; curvilinear velocity) was measured using computer-assisted
 sperm analysis, and sperm number was estimated using an Improved Neubauer
 hemocytometer.
description: The readme file contains an explanation of each of the variables
 in the dataset and (if applicable) their measurement units.