DOI: 10.5061/dryad.hhmgqnkm1
title: Per capita sperm metabolism is density-dependent

description: From bacteria to metazoans, higher-density populations have lower per
 capita metabolic rates than lower-density populations. This relationship
 between density and metabolism was actually first proposed 100 years ago
 and was focused on spermatozoa but contemporary studies of sperm
 metabolism specifically assume that sperm concentration has no effect on
 metabolism. We did a systematic review to estimate the relationship
 between sperm aerobic metabolism and sperm concentration, for 203
 estimates spanning 49 species, from protostomes to humans from 89 studies.
 We found strong evidence that per capita metabolic rates are
 concentration-dependent: both within- and among-species, sperm have lower
 metabolisms in dense ejaculates but increase their metabolism when
 diluted. On average, a 10-fold decrease in sperm concentration
 increased per capita metabolic rate by ~60%. Metabolic
 plasticity in sperm may be an adaptive response but this requires further
 testing.
description: Manuscript Title: Per capita sperm metabolism is density-dependent
 Authors: Ashley Potter, Craig White, Dustin Marshall Date updated: Tue 28
 February 2023 This file contains information for all the datasets in the
 manuscript and can be used with 'RDE-Data-Accessibility.Rmd' and
 'Supplemental_24_02.docx' NOTE: For all datasets, NA's
 indicate no data in the cell ## Please contact Ashley Potter if there are
 any other questions or concerns ashley.ashpot.potter (at) gmail.com #
 Title of Dataset1: Density-dependent sperm metabolism ## Csv name:
 RDE\_data.csv This dataset contains data on density-dependent sperm
 metabolism - how sperm metabolism changes across density ## Description of
 the Data and file structure Column names and descriptions * Species *
 Diluent_cat2: Diluent used to dilute sperm to a known concentration *
 Phyla * Class * Order * Family * LNConc: actual sperm concentration (sperm
 per ml) that was used when metabolism was measured - [natural log
 transformed] * LNMR: actual metabolic rate (microliters O2 per conc per
 hour) that was measured using the actual sperm concentration - [natural
 log transformed] * LNpercap: per captia sperm metabolic rate (microliters
 O2 per spermatozoon per hour) - [natural log transformed] * logConc:
 actual sperm concentration (sperm per ml) that was used when metabolism
 was measured - [log10 transformed] * logMR: actual metabolic rate
 (microliters O2 per conc per hour) that was measured using the actual
 sperm concentration - [log10 transformed] * logpercap: per captia sperm
 metabolic rate (microliters O2 per spermatozoon per hour) - [log10
 transformed] * Diluent_job: The job of the diluent. Used for sperm
 activation or extending sperm * Extraction: Method of sperm extraction
 (ejaculated, extracted from the male or extracted from the female
 (stored)) * Sperm_MR_Note: Was sperm concentration transformed or was
 there no transformation needed? * reference_MR: reference used to extract
 sperm metabolism data * ref_number: number corresponding to the
 reference_MR * Sperm_SD: Standard deviation of each measurement *
 Sperm_SEM: Standard error of the mean for each measurement * sample_size:
 Sample size used in each reference * Fresh_or_Frozen: Sperm handling
 method. Was MR measured on fresh, frozen-thawed or cooled sperm? *
 Endotherm_Ectotherm: Classified species as Endotherm or Ectotherm *
 Internal_External: Classified species as Internal or External *
 matched.species: species list for phylogeny * Carbs: Contents of the
 diluent (carbohydrate-free or carbohydrate-containing) * Sugar: Contents
 of the diluent shortened form (NS = No sugar, S = sugar) ## Sharing/access
 Information Data was collected from external sources which are references
 in the supplemental material Tables S1 and S3. --- # Title of phylogenetic
 tree: Phylogenentic tree that was used to run phylogenetic anayses ## Csv
 name: RDE\_tree.nwk This represents the phylogenetic tree made from Open
 Tree of Life that was used in the phyogenetic analyses --- # Title of
 Dataset2: Sperm misestimation dataset ## Csv name: Misestimation.csv This
 dataset was used to determine the percent misestimation of sperm
 metabolism based on the fold change in reported sperm concentration
 relative to the actual sperm concentration ## Description of the Data and
 file structure Column names and descriptions: * Actual_Conc: actual sperm
 concentration - sperm concentration (sperm per ml) that metabolism was
 measured at * Stand_Conc: standardised concentration - concentration used
 to transform the metabolic rate using a standardised sperm concentration *
 Actual_MR: actual metabolic rate (microliters O2 per sperm concentration
 per h) that was measured using the actual sperm concentration * Stand_MR:
 standardised metabolic rate (microliters O2 per sperm concentration per h)
 that was reported in the paper but used a standardised concentration * a -
 alpha: calculated using equation (2) in main text * R - Respiration rate:
 calculated using equation (1) in main text * Mis - misestimation:
 calculated using equation (3) in main text * Percent_mis: Mis * 100 *
 Fold_IncDec: Fold change in concentration - calculated using equation (4)
 in main text * LogFold_IncDec: log10(Fold_IncDec) --- # Title of Dataset3:
 Density-dependent estimates ## Csv name: densitydep\_slopes.csv This
 dataset was used to compare the mean scaling exponents of
 density-dependent metabolism between spermatozoa, multicellular and
 unicellular organisms ## Description of the Data and file structure Column
 names and descriptions * Type = Classification of Multicellular,
 unicellular or spermatozoa * Ref = reference data was extracted from *
 Slope = slope of the relationship between per-capita metabolic rate and
 population density --- # Title of Dataset4: Density-dependent sperm
 motility ## Csv name: RDE\_motility.csv This dataset was used to
 understand the relationship between sperm density (sperm/ml) and motility
 (%) ## Description of the Data and file structure Column names and
 descriptions * Motility_Percent: Percent motility that was recorded at
 initial activation of sperm * Sperm_Conc: Sperm concentration (sperm per
 ml) that was used during measurements of sperm motility, velocity or both
 * VCL: Curvilinear velocity (micrometers per second) * VAP: Average path
 velocity (micrometers per second) * VSL Straight line velocity
 (micrometers per second) * MR.measures.: Does this references have
 concurrent measures of sperm metabolism (Y/N)? * reference_MR: Reference
 used to extract metabolic rate data * Ref_Vel_Mot: Reference used to
 extract motility data, velocity data or both ## Sharing/access Information
 Data from external sources was cited