DOI: 10.5061/dryad.tdz08kpzr
title: Data from: A novel degree of sex difference in laryngeal physiology of Xenopus muelleri: behavioral and evolutionary implications

description: Characterizing sex and species differences in muscle physiology can
 contribute to a better understanding of proximate mechanisms underlying
 behavioral evolution. In Xenopus, the laryngeal muscle’s ability to
 contract rapidly and its electromyogram potentiation allows males to
 produce calls that are more rapid and intensity-modulated than female
 calls. Prior comparative studies have shown that some species lacking
 typical male features of vocalizations sometimes show reduced sex
 differences in underlying laryngeal physiology. To further understand the
 evolution of sexually differentiated laryngeal muscle physiology and its
 role in generating behavior, we investigated sex differences in the
 laryngeal physiology of X. muelleri, a species in which male and female
 calls are similar in rapidity but different with respect to intensity
 modulation. We delivered ethologically relevant stimulus patterns to ex
 vivo X. muelleri larynges to investigate their ability to produce various
 call patterns, and we also delivered stimuli over a broader range of
 intervals to assess sex differences in muscle tension and electromyogram
 potentiation. We found a small but statistically significant sex
 difference in laryngeal electromyogram potentiation that varied depending
 on the number of stimuli. We also found a small interaction between sex
 and stimulus interval on muscle tension over an ethologically relevant
 range of stimulus intervals; male larynges were able to produce similar
 tensions to female larynges at slightly smaller (11–12 ms) inter-stimulus
 intervals. These findings are consistent with behavioral observations and
 present a previously undescribed intermediate sex difference in Xenopus
 laryngeal muscle physiology.
description: All csv files including acoustic data (Pattern_IM,
 Pattern_Interval, Pulse_Numbers, patternAspectrogram, and
 patternBspectrogram) come from audio recordings from male X. muelleri
 only. All other files include data compiled from both males and females.
 Acoustic data was obtained using Audacity (v. 2.3.0, audacityteam.org)
 computer software and electrophysiology data was obtained using
 LabChart (v. 8.0.10, ADInstruments) computer software. 
description: This South_Xmuelleri_Readme.txt file was generated on 2021-02-22
 by Kelly South 2. Author Information<br>     A.
 Principal Investigator Contact Information<br>         Name: Dr.
 Elizabeth Leininger<br>         Institution: New College of
 Florida<br>         Address: <br>         Email:
 eleininger@ncf.edu     B. Associate or Co-investigator
 Contact Information<br>         Name: Kelly South<br>       
  Institution: New College of Florida<br>         Address: <br>
         Email: kelly.south15@ncf.edu 3. Date of data
 collection: 2018/01/15-2019/05/17 4. Geographic
 location of data collection: New College of Florida, Sarasota, FL, 34243
 USA 5. Information about funding sources that supported
 the collection of the data: Internal funding from New College of Florida
 and the New College Women's Giving Circle
 <br> SHARING/ACCESS INFORMATION 1.
 Licenses/restrictions placed on the data: NA 2. Links
 to publications that cite or use the data: NA 3. Links
 to other publicly accessible locations of the data: NA
 4. Links/relationships to ancillary data sets: NA
 5. Was data derived from another source? No 6.
 Recommended citation for this dataset:  <br> DATA
 & FILE OVERVIEW 1. File List: <br>
 Male_Female_Weights.csv            Body mass (g) and larynx mass (g) for
 all tested individuals<br> ApproachPI.csv                Average
 electromyogram potentiation index for approach call trains<br>
 patternAspectrogram.csv            Spectral information for recorded
 pattern A calls<br> patternBspectrogram.csv            Spectral
 information for recorded pattern B calls<br> Pulse_Numbers.csv      
      Distribution of pulse numbers per call<br> Pattern_IM.csv      
          Average intensity modulation for each call pattern<br>
 Pattern_Interval.csv            Average inter-call interval and
 inter-pulse interval for each call pattern<br> PTTdata.csv          
      Percent transient tension for tested inter-stimulus intervals and the
 order of stimulation (sequence)<br> EMGdata.csv              
  Potentiation index for tested inter-stimulus intervals and the order of
 stimulation (sequence) <br> 2. Relationship
 between files, if important:  3. Additional related
 data collected that was not included in the current data
 package:  4. Are there multiple versions of the
 dataset? No <br> METHODOLOGICAL
 INFORMATION 1. Description of methods used for
 collection/generation of data: Data collection and analysis based on
 experimental protocols from Leininger et al, (2015) and Tobias and Kelley,
 (1987)<br> Leininger, E. C., Kitayama, K. and Kelley, D. B. (2015).
 Species-specific loss of sexual dimorphism in vocal effectors accompanies
 vocal simplification in African clawed frogs (Xenopus). J. Exp. Biol. 218,
 849–857.<br> Tobias, M. L. and Kelley, D. B. (1987). Vocalizations
 by a sexually dimorphic isolated larynx: peripheral constraints on
 behavioral expression. J. Neurosci. 7, 3191–3197. 2.
 Instrument- or software-specific information needed to interpret the data:
 NA 3. Standards and calibration information, if
 appropriate: NA 4. Environmental/experimental
 conditions: Audio recorded from frogs in 22-23 degrees C 4%
 Holtfreter's solution. Electrophysiology experiments conducted in
 chilled (10 degrees C) dextrose-supplemented Ringer's
 solution 5. Describe any quality-assurance procedures
 performed on the data: NA 6. People involved with
 sample collection, processing, analysis and/or submission: Kelly
 South <br> DATA-SPECIFIC INFORMATION FOR:
 ApproachPI.csv 1. Number of variables: 2
 2. Number of cases/rows: 12 3. Variable
 List: <br> Sex<br> PI (potentiation index - analysis of the
 increase or decrease of strength of electrical impulses delivered,
 measured by dividing the amplitude difference between the maximum
 electromyogram and the first electromyogram (B-A) by the maximum value of
 the first electromyogram (A); (B-A)/A) 4. Missing data
 codes: NA 5. Specialized formats or other abbreviations
 used: NA <br> DATA-SPECIFIC INFORMATION FOR:
 EMGdata.csv 1. Number of variables: 6
 2. Number of cases/rows: 356 3. Variable
 List: <br> Frog<br> Sex<br> ISI (inter-stimulus interval
 - amount of time between two stimulations within an electrophysiological
 experiment - measured in milliseconds)<br> Burst (first stimulation
 denoted as 1, average of subsequent stimulations denoted as 2 - separated
 due to significant differences in response to electrical
 stimulation)<br> PI (potentiation index)<br> Sequence
 (randomized order of ISI delivered to each individual)
 4. Missing data codes: NA 5. Specialized
 formats or other abbreviations used: NA <br>
 DATA-SPECIFIC INFORMATION FOR: Male_Female_Weights.csv
 1. Number of variables: 3 2. Number of
 cases/rows: 16 3. Variable List: <br>
 Sex<br> Body (body mass measured in grams)<br> Larynx (larynx
 mass measured in grams) 4. Missing data codes:
 NA 5. Specialized formats or other abbreviations used:
 NA <br> DATA-SPECIFIC INFORMATION FOR:
 Pattern_IM.csv 1. Number of variables: 3
 2. Number of cases/rows: 6 3. Variable
 List: <br> Frog<br> Measure (Intensity modulation (IM)- Change
 in amplitude from first sound pulse (A) to highest intensity sound pulse
 (B) in a single call, measured by dividing the difference in maximum
 amplitude of the highest intensity sound pulse and first sound pulse by
 the maximum amplitude of the first sound pulse; (B-A)/A)<br> Pattern
 (vocal pattern recorded) 4. Missing data codes:
 NA 5. Specialized formats or other abbreviations used:
 NA <br> DATA-SPECIFIC INFORMATION FOR:
 Pattern_Interval.csv 1. Number of variables:
 4 2. Number of cases/rows: 12 3.
 Variable List: <br> Frog<br> Interval (Inter-call interval
 (ICI)- Amount of time between the first sound pulse of a call and the
 first sound pulse of the following call, and Inter-pulse interval (IPI) -
 Amount of time between sound pulses in a single call)<br>
 Measurement (time difference measured in milliseconds)<br> Pattern
 (vocal pattern associated with measurements) 4. Missing
 data codes: NA 5. Specialized formats or other
 abbreviations used: NA <br> DATA-SPECIFIC
 INFORMATION FOR: patternAspectrogram.csv and
 patternBspectrogram.csv 1. Number of variables:
 5 2. Number of cases/rows: 771 3.
 Variable List: <br> Frog<br> Hz (Raw frequency from audio
 recordings)<br> before (Background frequency)<br> Frequency
 (Normalized frequency)<br> Power (Relative amplitude of the
 frequency) 4. Missing data codes: NA
 5. Specialized formats or other abbreviations used: NA
 <br> DATA-SPECIFIC INFORMATION FOR: PTTdata.csv
 1. Number of variables: 5 2. Number of
 cases/rows: 178 3. Variable List: <br>
 Frog<br> Sex<br> ISI (inter-stimulus interval - amount of time
 between two stimulations within an electrophysiological experiment -
 measured in milliseconds)<br> PTT (percent transient tension -
 analysis of the amount of tension present in the laryngeal muscle tendon
 for a given IPI, measured by dividing the difference between the first
 maximum peak tension (a) and the minimum trough tension (t) by the
 difference between the first maximum peak tension (a) and the baseline
 (bl); [(a-t)/(a-bl)]*100%)<br> Sequence (randomized order of ISI
 delivered to each individual) 4. Missing data codes:
 NA 5. Specialized formats or other abbreviations used:
 NA DATA-SPECIFIC INFORMATION FOR:
 Pulse_Numbers.csv 1. Number of variables: 3
 2. Number of cases/rows: 13 3. Variable
 List: <br> PulseNumber (number of pulses found in a single call
 throughout audio recordings)<br> Total (total number of calls
 produced in audio recordings with that pulse number)<br> Pattern
 (vocal pattern assigned to the pulse number) 4. Missing
 data codes: NA 5. Specialized formats or other
 abbreviations used: NA