DOI: 10.5061/dryad.6djh9w1dx
title: Data from: City lizards are more social

description: Cities are expanding globally, exposing animals to novel ecological
 conditions that can alter the frequency and nature of their social
 interactions. Urban habitat features, such as built infrastructure and
 patchy resource distributions, can constrain movement and promote
 aggregation, potentially increasing encounters among conspecifics and
 introducing unique social challenges. Understanding how urbanization
 affects social behaviour is crucial. However, these effects remain poorly
 understood, and studies on solitary or non-gregarious species are
 particularly scarce. Here, we investigate how urbanization influences
 social behaviour in the Common wall lizard (Podarcis muralis), a
 territorial species and successful urban dweller. We constructed social
 networks from proximity-based association data from urban and non-urban
 lizard populations. Urban lizards had more social connections, stronger
 associations, and were observed in more associations overall. These
 differences were not explained by variation in population density. We
 propose that spatial constraints and resource heterogeneity in urban
 habitats may enhance social tolerance. Our results reveal that
 urbanization can reshape social behaviour even in less gregarious species,
 and suggest that shifts in social strategies may facilitate persistence in
 urban landscapes.
description: # Data Description: City lizards are more social **Authors:** Avery L.
 Maune, Tobias Wittenbreder, Duje Lisičić, Barbara A. Caspers, Ettore
 Camerlenghi, Isabel Damas-Moreira --- A total of 13 data files were used
 to construct and analyze social networks, including: `P1_GBI.csv` -
 `P6_GBI.csv`: Group-by-individual matrices `P1_attributes.csv` -
 `P6_attributes.csv`: Attribute metadata `sna_data.csv`: Combined dataset
 including calculated social metrics Only individuals observed ≥3 times (N
 = 69) are included in these files. Additional files included:
 `associations_data.csv`: Contains data for all marked individuals (N =
 94), used to analyze observation and association counts.
 `population_density.csv`: Lizard count data from line transect surveys
 conducted over 10 days across all size transects, used to estimate
 population density. `script_Maune_etal_SNA.R`: Full R script used for
 social network construction and statistical analysis ## Data files ### 1.
 Group-by-individual matrices Binary matrices showing individual
 co-occurrence in observed social groups. **Files:** `P1_GBI.csv`,
 `P2_GBI.csv`, `P3_GBI.csv`, `P4_GBI.csv`, `P5_GBI.csv`, `P6_GBI.csv`
 **Details**: Rows = observation events; Columns = individual lizards; 1 =
 present; 0 = absent ### 2. Attribute tables Metadata for each individual
 included in the social network analysis, including id, transect, habitat,
 and sex. The row order corresponds to the columns in the GBI matrices.\
 **Files:** `P1_attributes.csv` `P2_attributes.csv` `P3_attributes.csv`
 `P4_attributes.csv` `P5_attributes.csv` `P6_attributes.csv` ### 3. Social
 network dataset Combined data for all individuals (N = 69), including
 calculated social network metrics: `binary_degree` and `weighted_degree`.
 Social network metrics were calculate from the GBI matrices and added to
 the corresponding attribute tables, which were then combined into a single
 dataset for analysis.\ **File:** `sna_data.csv` ### 4. Association data
 Frequency of observations and associations for all marked individuals (N =
 94). Includes id, transect, habitat, the total number of associations
 (`asso_count`) and total observation events (`obs_count`) per individual.\
 **File:** `associations_data.csv` ### 5. Population density data Counts of
 lizards observed during 10 line transect surveys per site. Used to
 estimate population density across urban and non-urban habitats.\
 **File:** `population_density.csv` ### 6. R code Contains all R code used
 in the social network construction and statistical analysis.\ **File:**
 `script_Maune_etal_SNA.R` --- ## Variables | Variable | Description | |
 ----------------- |
 --------------------------------------------------------------------------- | | `id` | Unique lizard identifier | | `transect` | Transect ID (`P1`–`P6`) | | `habitat` | Habitat type: `urban` or `non_urban` | | `sex` | Sex class: `F` (female), `M` (male), or `Sub` (subadult) | | `asso_count` | Number of associations per individual (with marked or unmarked individuals) | | `obs_count` | Number of observations per individual | | `no_liz` | Number of lizards counted during a single transect survey | | `binary_degree` | Number of unique social connections per individual (network metric) | | `weighted_degree` | Sum of edge weights per individual (network metric) |