DOI: 10.5061/dryad.qjq2bvqqc
title: Data from: Elevated human impact on islands increases the introduction and extinction status of native insular reptiles

description: In the Anthropocene, the ranges of introduced species are expanding, while
 extinction-prone species are contracting. Introductions and extinctions
 are caused by how species respond to human impacts, but it is unknown why
 the ranges of some species expand and some contract. Here, we test whether
 this opposite response of human impact is due to introduced and
 extinction-prone species falling at opposite ends of geographic,
 evolutionary, or ecological trait continua. We constructed a database of
 native range maps, traits, phylogenetic relationships, and the
 introduction and extinction-prone status of squamate reptiles with ranges
 native to the Western Hemisphere. Across &gt;3,000 snake and lizard
 species (88% of known native squamates), 142 had been introduced elsewhere
 and 483 were extinction-prone (i.e., vulnerable, endangered, critically
 endangered, extinct in the wild, extinct). To explain variation in status,
 we first tested if the same human-impacted regions in the Americas
 contained the native ranges of species of either status. Second, we tested
 for phylogenetic signal in species status. Finally, we tested the
 explanatory power of multiple trait continua. The native ranges of
 introduced and extinction-prone reptiles were clustered in island regions
 with high human impact vs. mainland regions with lower human impact.
 Phylogenetic signal was weak for status, but introduced and
 extinction-prone species were clustered in different clades. All
 geographic and ecological traits that explained each status supported the
 opposite ends hypothesis. Introduced species had larger, edgier ranges,
 while extinction-prone species had smaller, simpler ranges. Introduced
 species were mostly herbivorous/omnivorous, while extinction-prone species
 were mostly carnivorous. Introduced species produced larger clutches,
 while extinction-prone species had smaller body sizes. In the
 Anthropocene, the naive ranges of introduced and extinction-prone species
 are in the same human-impacted regions where trait continua, having
 opposite effects, determine whether species ranges expand or contract in
 the continuing face of global change.
description: # Elevated human impact on islands increases the introduction and
 extinction status of native insular reptiles
 [https://doi.org/10.5061/dryad.qjq2bvqqc](https://doi.org/10.5061/dryad.qjq2bvqqc) ## Files 1. *JesseEcography2024WestHemiSquamatePhylogeny.nwk* - Newick format phylogeny of Western Hemisphere squamates 2. *JesseEcography2024WestHemiSquamateVariables.csv* - comma delimited file of the derived variables used in the study. ## Metadata The variables in JesseEcography2024WestHemiSquamateVariables.csv are 1. **Tip_labels** * **Description**: Unique identifier for each species in the phylogeny. * **Type**: Categorical (string) * **Example values**: Abronia_anzuetoi, Abronia_aurita 2. **Genus** * **Description**: Genus name of the species. * **Type**: Categorical (string) * **Example values**: Abronia 3. **Species** * **Description**: Full species name including genus and specific epithet. * **Type**: Categorical (string) * **Example values**: Abronia anzuetoi, Abronia aurita 4. **Stem_age** * **Description**: The stem age of the genus, indicating the time since the most recent common ancestor. * **Type**: Numeric (float) * **Range**: 0.003346 - 174.429250 5. **manual_category_merged** * **Description**: IUCN threat category * **Type**: Categorical (string) * **Example values**: VU (Vulnerable), EN (Endangered), CR (Critically Endangered) 6. **threat_bin1** * **Description**: Binary variable indicating if the species is considered threatened (1) or not (0). * **Type**: Numeric (integer) * **Range**: 0 - 1 7. **Introduced_bin** * **Description**: Binary variable indicating if the species is introduced (1) or not (0). * **Type**: Numeric (integer) * **Range**: 0 - 1 8. **area** * **Description**: Native range size of the species in square kilometers. * **Type**: Numeric (float) * **Range**: 0.001135 - 19569.164493 9. **norm.perimeter** * **Description**: Normalized perimeter of the species' range, indicating range shape (compactness versus edginess). * **Type**: Numeric (float) * **Range**: -0.991804 - 5.223306 10. **Insularity_cont** * **Description**: Portion of the species range located on oceanic islands. * **Type**: Numeric (float) * **Range**: 0.0 - 1.0 11. **area_evo** * **Description**: Evolutionary range expansion rate of the genus. * **Type**: Numeric (float) * **Range**: 1011.187003 - 2.217933e+10 12. **PC1** * **Description**: First principal component from PCA on climatic variables, aligned with climatic seasonality. * **Type**: Numeric (float) * **Range**: -4.379105 - 4.528202 13. **PC2** * **Description**: Second principal component from PCA on climatic variables, aligned with elevation-derived variables. * **Type**: Numeric (float) * **Range**: -2.396485 - 4.424098 14. **corrected_SD** * **Description**: Standard deviation of climatic variability within the species range, adjusted for range size. * **Type**: Numeric (float) * **Range**: -0.795953 - 6.494254 15. **parity** * **Description**: Binary variable indicating reproductive mode, with 1 for viviparous and 0 for oviparous. * **Type**: Numeric (integer) * **Range**: 0 - 1 16. **diet** * **Description**: Dietary category of the species (Carnivorous, Herbivorous, Omnivorous). * **Type**: Categorical (string) * **Example values**: Carnivorous, Omnivorous 17. **log_length_max** * **Description**: Natural log-transformed maximum body length of the species. * **Type**: Numeric (float) * **Range**: 1.171183 - 4.465908 18. **log_clutch_size** * **Description**: Natural log-transformed clutch size of the species. * **Type**: Numeric (float) * **Range**: 0.000000 - 2.484907 19. **worldports** * **Description**: Number of sea ports within the species' native range. * **Type**: Numeric (float) * **Range**: 0.0 - 49.0 20. **HFP_median** * **Description**: Median human footprint index within the species' range, indicating the level of human impact. * **Type**: Numeric (float) * **Range**: 0.0 - 49.999996 Missing data code: NA