DOI: 10.5061/dryad.np5hqc051
title: Data and code from: Male sea lamprey countersignal relative to their baseline pheromone but not the intensity of rivals’ signals

description: Animals signalling to potential mates inadvertently reveal information to
 sexual rivals. In species that communicate with visual or acoustic
 signals, rivals are well-documented to use this information to optimize
 their signalling strategy based on the current level of competitive risk.
 We studied how males fine-tune their signals after exposure to varying
 levels of simulated competition in a species that relies on chemical
 signals, the sea lamprey (Petromyzon marinus). Sea lamprey aggregate on
 spawning grounds in streams, where males each build a nest and signal to
 females using the sex pheromone 3-keto petromyzonol sulphate (3kPZS). We
 hypothesized that males use the concentration of environmental 3kPZS to
 infer the level of competitive risk and adjust their 3kPZS release
 proportionally. Males increased 3kPZS release after exposure to 3kPZS,
 but, contrary to our hypothesis, the change in release was similar across
 concentrations from 5 x 10-7 M down to 5 x 10-13 M. Interestingly, the
 increase in 3kPZS release after exposure to 3kPZS was negatively
 correlated with baseline release rates. Taken together, our results
 indicate that male sea lamprey adjust their pheromone signals based on the
 presence of rivals and their baseline signal, but not any graded
 assessment of competition risk.
description: # Male sea lamprey countersignal relative to their baseline pheromone, but
 not the intensity of rivals' signals **Included files** * DR Exposure
 Analyses.csv. This file includes raw data for the study. * DR Exposure
 Analyses_script. R script for the analyses. This script analyzes how male
 sea lampreys alter their 3kPZS pheromone release in response to varying
 doses and social cues across multiple years (2016, 2017, 2021), using
 nonparametric longitudinal models, post hoc comparisons, correlation
 analyses, and visualization of pheromone change relative to baseline. #
 Description of the data and file structure * Males were sampled in 2016,
 2017, and 2021. Data are also included from Fissette et al., 2020. Journal
 of Experimental Biology 223, jeb226647. * Fish ID Trt./Exp. Fish ID in the
 treatment and experiment * Global.ID- Overall fish ID * Treatment is
 either a vehicle control (50% methanol: water) or the male pheromone
 3-keto petromyzonol sulfate (3kPZS). 3kPZS treatments are molar
 concentrations (seven through sixteen). * Time is whether the sample was
 from before exposure to 3kPZS or 10 minutes after. Before exposure,
 samples were collected after a male conditioned the water for 30 minutes.
 * ng/mL is the nanograms of 3kPZS per milliliter of water. * The
 difference is the change in ng.ml from the previous time point. For time
 0, the change is just the concentration. For time 10, it is the difference
 in ng.ml from time 10 and time 0. * ng.h is the back-calculated release
 rate in nanograms per hour. For time 0, mg.h = ng.ml x 3000 (vol) x 2
 (convert 30 min release rate to 1 h release rate) * mg.h is the release
 rate in milligrams per hour (ng.h / 1,000,000) * Length is the total body
 length in mm. * Weight is mass in g