DOI: 10.5061/dryad.z08kprrpr
title: Sumatran orangutan mothers differ in the extent and trajectory of their expression of maternal behaviour

description: Mothers play a crucial role in the early development and survival of
 mammalian offspring, and differences in maternal care may differentially
 affect offspring’s development. Whereas previous research has primarily
 focused on biological and socioecological factors to understand
 population-level variation in maternal behaviour, the individual as a
 source of variation remains understudied. We investigated
 between-individual variation in the average expression of, and plasticity
 in, six maternal behaviours in Sumatran orangutans, using 15 years of
 behavioural data. We found that mothers differed substantially in the
 average expression of four maternal behaviours, even after controlling for
 socioecological conditions, biological state characteristics, and the
 offspring’s influence on these behaviours. Furthermore, not controlling
 for these confounding effects exaggerated or masked between-individual
 variation. Mothers also substantially differed in how they adjusted three
 of the maternal behaviours during offspring development, meaning that
 mothers differed in behavioural plasticity. Our results suggest that
 Sumatran orangutan mothers are constrained in the average expression of
 maternal behaviours and their plastic responses, potentially resulting in
 consistent differences among mothers, otherwise called maternal
 personality. Our findings highlight that individual variation around the
 population mean in maternal behaviour is more than noise and presents
 opportunities to study novel evolutionary processes that shape maternal
 behaviour.
description: # Sumatran orangutan mothers differ in the extent and trajectory of their
 expression of maternal behaviour
 [https://doi.org/10.5061/dryad.z08kprrpr](https://doi.org/10.5061/dryad.z08kprrpr) ## Description of the data and file structure ### Paper Sumatran orangutan mothers differ in the extent and trajectory of their expression of maternal behaviour ### Description of the data and file structure This README file describes the columns of the TXT data files accompanying the above publication. The TXT file collects the maternal behaviour data: carry, contact initiation, contact termination, close proximity initiation, close proximity termination, feeding in close proximity; estimates; and sample size All analyses were performed in R. **Version** 1.1 ### Files and variables #### File: carry.txt **Description:** Data on maternal behaviour *carry* used in the analysis. ##### Variables * followNr: ID assigned to follow in the database * followType: Type of follow: NN: nest-to-nest; NL: nest-to-lost; FN: found-to-nest; FL: found-to-lost * followDate: Date during which the follow took place * duration: Duration of the follow (in hours) * motherID: ID assigned to the focal mother * offspringID: ID assigned to the focal mother's offspring * offspringAge: Age of the offspring * offspringSex: Sex of the offspring * males_P_A: Male presence/absence in association with the focal mother-offspring pair * FAI: Food availability index * assoc_size: Association size of the focal mother-offspring pair * no_of_times_mother_moves: Total no. of scans in which the mother moved during a follow * no_of_times_mother_carries: No. of scans in which the mother carried her offspring during a follow #### File: close\_proximity\_initiation.txt **Description:** Data on maternal behaviour *close proximity initiation *used in the analysis. ##### Variables * followNr: ID assigned to follow in the database * followType: Type of follow: NN: nest-to-nest; NL: nest-to-lost; FN: found-to-nest; FL: found-to-lost * followDate: Date during which the follow took place * duration: Duration of the follow (in hours) * motherID: ID assigned to the focal mother * offspringID: ID assigned to the focal mother's offspring * offspringAge: Age of the offspring * offspringSex: Sex of the offspring * males_P_A: Male presence/absence in association with the focal mother-offspring pair * FAI: Food availability index * assoc_size: Association size of the focal mother-offspring pair * no_of_scans_within_5_50m: Total no. of scans in which the mother and offspring were not in close proximity (i.e., &gt;5-&lt;=50 m) during a follow * no_of_times_mother_initiated_cp: No. of scans in which the mother initiated close proximity with her offspring (&gt;5-&lt;=50 m to &lt;=5 m but no body contact) during a follow #### File: close\_proximity\_termination.txt **Description:** Data on maternal behaviour *close proximity termination *used in the analysis. ##### Variables * followNr: ID assigned to follow in the database * followType: Type of follow: NN: nest-to-nest; NL: nest-to-lost; FN: found-to-nest; FL: found-to-lost * followDate: Date during which the follow took place * duration: Duration of the follow (in hours) * motherID: ID assigned to the focal mother * offspringID: ID assigned to the focal mother's offspring * offspringAge: Age of the offspring * offspringSex: Sex of the offspring * males_P_A: Male presence/absence in association with the focal mother-offspring pair * FAI: Food availability index * assoc_size: Association size of the focal mother-offspring pair * no_of_scans_within_1_5_m: Total no. of scans in which the mother and offspring were in close proximity (i.e., &lt;=5 m, but no contact) during a follow * no_of_times_mother_terminated_cp: No. of scans in which the mother terminated close proximity with her offspring (&lt;=5 m, but no contact to &gt;5-&lt;=50 m) during a follow #### File: contact\_initiation.txt **Description:** Data on maternal behaviour *contact initiation *used in the analysis. ##### Variables * followNr: ID assigned to follow in the database * followType: Type of follow: NN: nest-to-nest; NL: nest-to-lost; FN: found-to-nest; FL: found-to-lost * followDate: Date during which the follow took place * duration: Duration of the follow (in hours) * motherID: ID assigned to the focal mother * offspringID: ID assigned to the focal mother's offspring * offspringAge: Age of the offspring * offspringSex: Sex of the offspring * males_P_A: Male presence/absence in association with the focal mother-offspring pair * FAI: Food availability index * assoc_size: Association size of the focal mother-offspring pair * no_of_scans_not_in_bc: Total no. of scans in which mother and her offspring were not in contact (i.e., &gt;0 m) during a follow * no_of_times_mother_initiated_bc: No. of scans in which the mother initiated body contact with her offspring (&gt;0 m to 0 m) during a follow #### File: contact\_termination.txt **Description:** Data on maternal behaviour *contact termiation *used in the analysis. ##### Variables * followNr: ID assigned to follow in the database * followType: Type of follow: NN: nest-to-nest; NL: nest-to-lost; FN: found-to-nest; FL: found-to-lost * followDate: Date during which the follow took place * duration: Duration of the follow (in hours) * motherID: ID assigned to the focal mother * offspringID: ID assigned to the focal mother's offspring * offspringAge: Age of the offspring * offspringSex: Sex of the offspring * males_P_A: Male presence/absence in association with the focal mother-offspring pair * FAI: Food availability index * assoc_size: Association size of the focal mother-offspring pair * no_of_scans_in_bc: Total no. of scans in which the mother and offspring were in contact (0 m) during a follow * no_of_times_mother_terminated_bc: No. of scans in which the mother terminated body contact with her (0 m to &gt;0 m) during a follow #### File: feeding\_in\_proximity.txt **Description:** Data on maternal behaviour *feeding in close proximity *used in the analysis. ##### Variables * followNr: ID assigned to follow in the database * followType: Type of follow: NN: nest-to-nest; NL: nest-to-lost; FN: found-to-nest; FL: found-to-lost * followDate: Date during which the follow took place * duration: Duration of the follow (in hours) * motherID: ID assigned to the focal mother * offspringID: ID assigned to the focal mother's offspring * offspringAge: Age of the offspring * offspringSex: Sex of the offspring * males_P_A: Male presence/absence in association with the focal mother-offspring pair * FAI: Food availability index * assoc_size: Association size of the focal mother-offspring pair * noofscans_infeedprox: No. of scans in which the mother was feeding within 5 m of her offspring who was also feeding on the same food item as its mother during a follow * noofscans_feeding: Total no. of scans during which the mother was feeding during a follow #### File: estimate\_w\_wo\_controlling.txt **Description:** Random intercept (mother identity) estimates from the models in which the fixed effects were and were not controlled. ##### Variables * Behaviour: Name of the behaviour * Behaviour_code: Behaviour code assigned to the behaviour (for x-axis); 1. body contact initiation, 2. body contact termination, 3. close proximity initiation, 4. close proximity termination, 5. carrying, and 6. feeding in close proximity * Estimate: Estimate obtained from the respective full model (full.wnc) and the model in which the estbalished predictors were not controlled (full.wnc.3) for each behaviour * l_CI: lower 95% CI of the estimate * u_CI: upper 95% CI of the estimate * Group: group indicating whether the data row is for predictor controlled or not controlled #### File: sample\_size\_data.txt **Description:** Data on sample size for the six maternal behaviours. ##### Variables * offspringID: ID assigned to the focal mother's offspring * no_of_follows: No. of follows of the mother-offspring pair for each behaviour * duration_of_follows: Duration of follows of the mother-offspring pair for each behaviour (in hours) * behaviour: Code assigned to the behaviour (for x-axis); BCI - body contact initiation, BCT - body contact termination, CAR - carry, CPI - close proximity initiation, CPT - close proximity termination, FCP - feeding in close proximity * behaviour: behaviour as numbers #### File: estimates\_correlation.txt **Description:** Estimates from the respective parsimonious model for the four behaviours with a significant effect of motherID to conduct a correlation test. ##### Variables * motherID: ID assigned to the focal mother * contact termination: estimate from full.wnc.1 model * close proximity termination: estimate from full.wnc model * carry: estimate from full.wnc model * feeding in proximity: estimate from full.wnc model #### File: carry\_w\_cov\_beta.Rmd **Description:** R code for analysis and graphs for the behaviour *carry* #### File: carry\_w\_cov\_beta\_filtered.Rmd **Description:** R code for analysis and graphs for the behaviour *carry *for the filtered data (only mothers with multiple offspring) #### File: close\_proximity\_initiation\_w\_cov.Rmd **Description:** R code for analysis and graphs for the behaviour *close proximity initiation* #### File: close\_proximity\_termination\_w\_cov.Rmd **Description:** R code for analysis and graphs for the behaviour *close proximity termination* #### File: close\_proximity\_termination\_w\_cov\_beta\_filtered.Rmd **Description:** R code for analysis and graphs for the behaviour *close proximity termination *for the filtered data (only mothers with multiple offspring) #### File: contact\_initiation\_w\_cov.Rmd **Description:** R code for analysis and graphs for the behaviour *contact* *initiation* #### File: contact\_termination\_w\_cov.Rmd **Description:** R code for analysis and graphs for the behaviour *contact* *termination* #### File: feeding\_in\_close\_proximity\_w\_cov\_beta.Rmd **Description:** R code for analysis and graphs for the behaviour *feeding in close proximity* #### File: feeding\_in\_close\_proximity\_w\_cov\_beta\_filtered.Rmd **Description:** R code for analysis and graphs for the behaviour *feeding in close proximity *for the filtered data (only mothers with multiple offspring) #### File: estimate\_w\_wo\_controlling.r **Description:** R code for graph to plot random intercept estimates from the models in which the fixed effects were and were not controlled #### File: sample\_size\_graphs.r **Description:** R code for graph to plot sample size for the six maternal behaviours #### File: estimates\_correlation.r **Description:** R code for graph to do a correlation test on motherID random intercepts for the four behaviours in which there was a significant effect of mother identity ## Code/software R environment version 4.2.2