Data and scripts from: Most mammals do not wander: few species escape continental endemism

Terrestrial mammals are found nearly everywhere on earth. Yet, most taxa are endemic to a single continent; geological, evolutionary, ecological or physiological filters constrain geographic distributions. Here, we synthesize data on geography, taxonomy, lineage age, dispersal, body size, and diet for >4,000 terrestrial mammals prior to detectable human-mediated biodiversity losses and quantify factors correlated with the likelihood of dispersal between continents. We confirm the uniqueness of being on multiple continents: excluding humans and commensals, only 260 mammals are found on two continents, while six span three or more continents (the red deer, red fox, brown bear, least weasel, and common bent-wing bat), and just a single species—the lion—once had a geographic range that included four continents. Clearly, the challenges of colonizing and persisting on multiple continents are severe. No single characteristic enables taxa to be on more than one continent. Rather, a suite of prerequisite conditions under some circumstances lead to distributions spanning multiple continents. Interestingly, the suite of factors facilitating the occupation of two continents, like being volant, is distinct from those that lead to the occupation of three or more, which are primarily faunivores. Other than humans and our commensals, very few species have become truly cosmopolitan over evolutionary time and geographic space.

Methods
Data Collection

We used the updated Body Mass of Late Quaternary Mammals dataset (Smith et al. 2003) to version 11.1. See supplemental information of manuscript for deatils. We additionally collected contitnet of family origin ("familyOrigin_Oct2024.csv"). We also added in generic first appearance from the PaleobioDB (see Analysis.R) and Faurby et al. 2018 (PHYLACINE). We also combined data about geographic range, home range, and age of dispersal from Jones et al. 2009 (PanTHERIA), natural ranges from Faurby et al. 2018 (PHYLACINE), as well as generation length from Pacifici et al. 2013. We do not republish existing datasets here.

Data cleaning

Data for Analysis

We removed all species records not on a continent (i.e., insular and marine species). We also removed non-native species, including introduced and domesticated species. This is in "Analysis.R" under "TRIM DATA".

Since we do not include previously published data, the script “Analysis.R” includes instructions for finding and uploading other datasets used.

Data Manipulation

All data manipulation can be found in "Analysis.R".

We first standardized diet categories under "FIX DIET". We then filled in missing diet by creating generic and above diet categories, under "MAKE GENERIC & FAMILY AVERAGES".

Analysis

The script for all analyses is "Balk_etal_GlobeTrotters.R". These include sections, "NUM SP PER CONTINENT", "CONNECTIVITY", "FAMILY ORIGIN", "DIVERSITY OF CLADE", "BODY SIZE:, "DIET", "HABITAT MODE", "DECISION TREE", "LOG ODDS", and "GEOGRAPHIC RANGE SIZE".