Data and code from: Male sea lamprey countersignal relative to their baseline pheromone but not the intensity of rivals’ signals
Data files
Jun 09, 2025 version files 53.30 KB
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DR_Exposure_Analyses_script.R
11.64 KB
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DR_Exposure_Analyses.csv
39.90 KB
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README.md
1.76 KB
Abstract
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.
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