Exotics Exhibit More Evolutionary History Than Natives

Helmus, Matthew R.; Behm, Jocelyn E.; Jesse, Wendy; Kolbe, Jason J.; Ellers, Jacintha; Losos, Jonathan B.

doi:10.1002/9781119072799.ch7

Cited by 6 publications

(2 citation statements)

References 76 publications

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“…We constructed a binomial variable to indicate whether a species was introduced anywhere on earth, and a response variable that indicated if a species was extinction-prone or not. To determine introduction status, we cross-referenced 3111 species from the phylogeny for which we had spatial native range data (see “Geographic data” below) with published invasive species databases, such as the Global Register of Introduced and Invasive Species, the Global Invasive Species Database, the Invasive Species Compendium, and others (e.g., Powell et al 2011, Mahoney et al 2015, Tingley et al 2016, Helmus et al 2017, Behm et al 2022; see Table S1 for the full list of references). For all species that did not match with these databases, we performed a Google query using the search term “ Species name AND introduced OR exotic OR invasive OR alien OR nonnative OR non-indigenous” to look for species-specific literature.…”

Section: Methodsmentioning

confidence: 99%

Elevated human impact on islands increases the introduction and extinction status of native insular reptiles

Jesse

Ellers

Behm

et al. 2022

Preprint

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The Anthropocene is marked by unprecedented changes to species ranges worldwide. Introduced species expand their native range into new geographic regions while extinction-prone species experience severe native range contraction. Introductions and extinctions are both caused by how species respond to human influence within their native ranges. The question arises if the opposite response in distributional change is due to introduced and extinction-prone species falling at opposite ends of geographic, evolutionary and ecological trait continua. Here, we assess the factors that explain the introduction and extinction-prone status for 3111 squamate reptile species native to the western hemisphere, of which 142 species have been introduced elsewhere and 483 species are threatened with extinction. We first asked what geographic regions contained the most introduced and extinction-prone species and if these species are evolutionarily related. We then tested the opposite ends hypothesis for several species characteristics. Our results show that the native ranges of introduced and extinction-prone reptiles are skewed towards island regions and that significant phylogenetic signal exists for these two groups, indicating they are not a random selection of the reptiles that have evolved in the western hemisphere. Species whose native ranges were more insular and were more influenced by humans were more likely to be introduced or extinction-prone. Evolutionary factors did not explain species status, but multiple geographic and ecological factors supported the opposite ends hypothesis. Introduced species were positively associated with herbivory and omnivory and had large and complex ranges, whereas extinction-prone species were generally carnivorous with small and simple ranges. In addition, introduced species produced larger clutches and extinction-prone species had relatively small body sizes. In the Anthropocene, the naive ranges of introduced and extinction-prone species are situated in the same human-impacted regions, but species range characteristics and functional traits determine whether species ranges expand or contract in the continuing face of global change.

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Section: Methodsmentioning

confidence: 99%

Elevated human impact on islands increases the introduction and extinction status of native insular reptiles

Jesse

Ellers

Behm

et al. 2022

Preprint

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“…The Anolis lizards have become an informative system for native/nonnative comparisons (e.g., Helmus et al., ). Twenty species of Anolis have established dozens of nonnative populations (Lever, ), and these species display a nonrandom set of characteristics (Latella, Poe, & Giermakowski, ).…”

Section: Introductionmentioning

confidence: 99%

Empirical test of the native–nonnative distinction: Native and nonnative assemblages of Anolis lizards are similar in morphology and phylogeny

Poe

Latella

2018

Functional Ecology

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Nonnative (“invasive,” “exotic,” “naturalized”) species frequently are vilified. However, some philosophers and ecologists have questioned whether nonnative species and assemblages are objectively, ahistorically identifiable as different entities relative to native species and assemblages, once selection biases are taken into account. We used an unprecedented dataset of morphology, phylogeny and assemblage content for 336 species of Anolis lizard to compare morphological and phylogenetic characteristics of variability and central tendency between native assemblages and those that include nonnative species. Equivalence tests demonstrated significant similarity between native and nonnative assemblages in trait variability, phylogenetic dispersion and mean trait values except for body size; logistic and zero‐inflated regression failed to distinguish native and nonnative assemblages. For most traits, similarity was not due to assemblages being structured randomly but rather to both native and nonnative assemblages including similar species. Without historical information, a naïve observer would be unable to identify Anolis assemblages as native or nonnative based on morphological assemblage structure or most mean assemblage trait values, but would have some success categorizing assemblages based on average body size of species in the assemblage. Significant phylogenetic and morphological clustering in native assemblages likely reflects source pools composed of close relatives that share traits, as well as some environmental filtering effects; the slightly less phylogenetically clustered but equally morphologically clustered nonnative assemblages are less constrained to proximal source pools but still probably subject to filtering. Differences between native and nonnative assemblages in mean body size likely reflect assemblage youth. The ontological status of nonnative species is discussed in the light of these results. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.13185/suppinfo is available for this article.

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