Data from: Functions of bidirectional sex change and simultaneously hermaphroditic phase gonads in the monogamous goby Lubricogobius exiguus
Data files
Jul 07, 2025 version files 44.37 KB
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Data_breeding_pair.csv
2.27 KB
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Data_egg.csv
1.04 KB
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Data_female_spawning_interval.csv
5.35 KB
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Data_soritay_inidividual.csv
2.28 KB
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Data_spawning.csv
11.41 KB
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Oyama_et_al._ethlogy_R.cord.R
15.71 KB
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README.md
6.30 KB
Abstract
Hermaphroditism has been widely confirmed in fish and includes four recognized types: protogyny, protandry, bidirectional sex change, and simultaneous hermaphroditism. Among these, bidirectional sex change and simultaneous hermaphroditism are considered the most flexible sexual patterns, due to their frequent switching of functional sexes. They are predicted to evolve under conditions of limited mating opportunities, such as low population density and mobility, and are thought to share common evolutionary factors. The goby Lubricogobius exiguus exhibits bidirectional sex change, with simultaneously hermaphroditic (SH) phase gonads, containing both developed testicular and ovarian tissues, particularly in females and solitary individuals. In this study, we conducted field observations to examine the mating system in L. exiguus and investigate the significance of its plastic sexual patterns. The results revealed that the goby randomly formed mating pairs, regardless of body size. Although a few pairs maintained long-term mating relationships over 70 days, approximately half of the pairs dissolved within 11 days. Under frequent partner changes in the non-size-assortative monogamy, the goby individuals rapidly established new mating pairs through bidirectional sex change using SH phase gonads. This sexual plasticity enabled L. exiguus to initiate reproduction quickly regardless of the sex of the partner, supporting the evolutionary predictions underlying bidirectional sex change and simultaneous hermaphroditism. In addition to the characteristics of the mating system, ecological traits such as being a microhabitat specialist on sandy-bottom substrates with a short lifespan may have influenced the evolution of the sexual pattern in L. exiguus.
Dataset DOI: 10.5061/dryad.pc866t21v
Description of the data and file structure
FILE Data breeding pair.csv
OVERALL DESCRIPTION:
This file contains the data of breeding pairs in Lubricogobius exiguus.
COLUMN EXPLANATION
- Pair ID: "Identification number of the breeding pair"
- Number of spawning: "Number of spawning observed in this study"
- Pair period: "Pairing period in each pair (day)"
- Male ID: "Identification number of male individual"
- Female ID: "Identification number of female individual"
- Male TL: "Total length of male individual (mm)"
- Female TL: "Total length of female individual (mm)"
- Size difference: "Absolute difference in total length between males and females in each pairs (mm)"
- Observation type: "Types of observed cases for each pair. F represents the entire observed pairing period, while P represents only a part of the observed pairing period."
- Cluster: "This variable represents the cluster assignment resulting from a cluster analysis based on two behavioral metrics: Pairing period and Number of spawning."
NOTE: "NA" (non-applicable) is included in various columns to reflect instances in which we were unable to record the respective information for that variable.
FILE Data sapwning.csv
OVERALL DESCRIPTION:
This file contains the results of observations on the spawning behavior of Lubricogobius exiguus.
COLUMN EXPLANATION
- Pair ID: "Identification number of the breeding pair"
- Male ID: "Identification number of male individual"
- Female ID: "Identification number of female individual"
- Nest ID: "Identification number of the nest"
- Spawning date: "Date of spawning or first egg confirmation (YYYY/MM/DD)"
- Hatching date: "Date of egg hatching or disappearance (YYYY/MM/DD)"
- Start time: "Start time of spawning behavior (HH:MM)"
- End time: "End time of spawning behavior (HH:MM)"
- Observation type: "Types of observed cases for each spawning event. F represents the entire observed spawning behavior, while P represents only a part of the observed spawning behavior."
- Spawning duration: "Duration of spawning behavior (min)"
- Sunrise time: "Sunrise time in Kagoshima, Japan (HH:MM)"
- Sunrise to spawning time: "Time from sunrise to the start of spawning behavior (min)"
NOTE: "NA" (non-applicable) is included in various columns to reflect instances in which we were unable to record the respective information for that variable.
FILE Data female spawning interval.csv
OVERALL DESCRIPTION:
This file contains the results of the female spawning interval of Lubricogobius exiguus.
COLUMN EXPLANATION
- Pair ID: "Identification number of the breeding pair"
- Female ID: "Identification number of female individual"
- Spawning date: "Date of spawning (YYYY/MM/DD)"
- Hatching date: "Date of egg hatching (YYYY/MM/DD)"
- FSI: "Female spawning interval (day)"
- HSS: "The days between hatching and subsequent spawning (day)"
NOTE: "NA" (non-applicable) is included in various columns to reflect instances in which we were unable to record the respective information for that variable.
FILE Data egg.csv
OVERALL DESCRIPTION:
This file contains data on the number of eggs from the breeding pairs of Lubricogobius exiguus.
COLUMN EXPLANATION
- Number of eggs: "Number of eggs in a cultch"
- Average number of eggs: "Average number of eggs in a cultch"
- Pair ID: "Identification number of the breeding pair"
- Female ID: "Identification number of female individual"
- Average female TL: "Average total length of female individual (mm)"
- Male ID: "Identification number of male individual"
- Average male TL: "Average total length of male individual (mm)"
NOTE: "NA" (non-applicable) is included in various columns to reflect instances in which we were unable to record the respective information for that variable.
FILE Data solitary individual.csv
OVERALL DESCRIPTION:
This file contains data on the solitary individuals of Lubricogobius exiguus.
COLUMN EXPLANATION
- Individual ID: "Identification number of individual"
- Solitary period: "Solitary period in each individual (day)"
- GMSS: "Gonadal morphological stage of solitary individual at the start of solitary status (NOS, non-developed ovary stage; DOS, developing ovary stage; MOS, matured ovary stage)"
- GMSE: "Gonadal morphological stage of solitary individual at the end of solitary status (NOS, non-developed ovary stage; DOS, developing ovary stage; MOS, matured ovary stage)"
- TND: "Time of transitions from NOS to DOS in solitary individual (day)"
- TNM: "Time of transitions from NOS to MOS in solitary individual (day)"
- COS: "Causes of the onset of solitary status in solitary individuals. Male refers to the disappearance of the male in the pair, female refers to the disappearance of the female in the pair, and unknown refers to individuals that were in a solitary state from the start of the observation."
- CES: "Causes of the end of solitary status in solitary individuals. Recruitment refers to other individual recruiting to the nests, while disappearance refers to the disappearance of a solitary individual."
- GMSR: "Gonadal morphological stage of recruited individual (NOS, non-developed ovary stage; DOS, developing ovary stage; MOS, matured ovary stage)"
- PCFS: "The period from the day the recruited individuals and former solitary individuals cohabited to the first day of spawning (day)"
- Pair ID: "Identification number of pair of solitary individuals that paired with recruited individuals"
NOTE: "NA" (non-applicable) is included in various columns to reflect instances in which we were unable to record the respective information for that variable.
FILE Oyama et al. ethology R.cord
OVERALL DESCRIPTION: This file contains the R script to perform the analyses and generate the figures in this study.
Code/software
All statistical analyses were performed using the R version 4.4.0 software (R Core Team 2024).
R Core Team. 2024. R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Available at https://www.R-project.org/