DOI: 10.5061/dryad.1c59zw41f
title: Data from: Paleoenvironments shaped the exchange of terrestrial vertebrates across Wallace’s Line

description: Faunal turnover in Indo-Australia across Wallace’s Line is one of the most
 recognizable patterns in biogeography and has catalyzed debate about the
 role of evolutionary and geoclimatic history in biotic interchanges. Here,
 analysis of over 20,000 vertebrate species with a model of geoclimate and
 biological diversification shows that broad precipitation tolerance and
 dispersal ability were key for exchange across the deep-time precipitation
 gradient spanning the region. Sundanian (Southeast Asian) lineages evolved
 in a climate similar to the humid ‘stepping stones’ of Wallacea,
 facilitating colonization of the Sahulian (Australian) continental shelf.
 In contrast, Sahulian lineages predominantly evolved in drier conditions,
 hampering establishment in Sunda, and shaping faunal distinctiveness. We
 demonstrate how the history of adaptation to past environmental conditions
 shapes asymmetrical colonization and global biogeographic structure.
 Faunal turnover in Indo-Australia across Wallace’s Line is one of the most
 recognizable patterns in biogeography and has catalyzed debate about the
 role of evolutionary and geoclimatic history in biotic interchanges. Here,
 analysis of over 20,000 vertebrate species with a model of geoclimate and
 biological diversification shows that broad precipitation tolerance and
 dispersal ability were key for exchange across the deep-time precipitation
 gradient spanning the region. Sundanian (Southeast Asian) lineages evolved
 in a climate similar to the humid ‘stepping stones’ of Wallacea,
 facilitating colonization of the Sahulian (Australian) continental shelf.
 In contrast, Sahulian lineages predominantly evolved in drier conditions,
 hampering establishment in Sunda, and shaping faunal distinctiveness. We
 demonstrate how the history of adaptation to past environmental conditions
 shapes asymmetrical colonization and global biogeographic structure.
description: All data was collated from
 published sources. <strong>Spatial and phylogenetic data for terrestrial
 vertebrates</strong> We obtained spatial and phylogenetic information
 for all 488 taxonomic families of birds, mammals, amphibians, and squamate
 reptiles, composed of 32,645 species. We obtained matching data on the
 geographic distribution and phylogenetic position of extant species of
 terrestrial vertebrates collected through the VertLife project
 (vertlife.org) in association with Map of Life
 (mol.org). We subset this
 data to include only families found in Sunda or Sahul. This data set
 contained matching phylogenetic and spatial data for 227 families composed
 of 20,433 species, with 7216 species of birds, 3551 amphibians, 6106
 reptiles, and 3560 mammals.
 <strong>Paleoenvironmental
 reconstruction</strong> Our reconstruction of paleogeographic evolution
 is based on maps from Hall 2013. From that study, we use the maps from 30 Ma to
 the present-day, which are presented at 5 Ma intervals. From these maps,
 we developed a continuous reconstruction of paleogeography in 0.1 Ma
 timesteps, incorporating plate tectonic motion and the spatial
 distribution of ocean, land, and highlands. We reconstructed paleoenvironmental temperature
 from the reconstructed distribution of Köppen climate bands
 (Scotese et al
 2021), corrected for
 elevation. We obtained
 reconstructed Köppen climate bands at 5 Ma intervals from 35 Ma to 0
 Ma. These broad climate
 bands are estimated from different fossil and lithological indicators and
 give a broad categorization of spatial variation in climate type
 (tropical, sub-tropical arid, warm temperate, cool temperate, and polar)
 and approximate the steepness of the latitudinal gradient in temperature
 through time. We assigned
 each Köppen climate band a temperature value based on present-day averages
 of those climate bands (tropical=26, sub-tropical arid=22, warm temperate
 = 16, cool temperate = 5, polar=-20). To account for global fluctuations
 in temperature, we then modify these average values by a global
 temperature change curve based on oxygen isotope data. Finally, to account for the decrease in
 temperature with increasing elevation, we use a lapse rate of 9.8 °C/km.
 We model variation in the
 intensity of temperature oscillations during the Pleistocene. We derived
 mean daily precipitation data from the global circulation model of
 paleoclimate from. This
 paleoclimatic data is based on a HadCM3L model, which couples ocean,
 atmosphere and vegetation and was simulated at 5 Ma
 intervals.
description: Data_S9.rds requires the R software to open: data &lt;-
 readRDS("Data_S9.rds")