Constraints on vertebrate range size predict extinction risk

Abstract China is a country with one of the most species rich reptile faunas in the world. However, nearly a quarter of Chinese lizard species assessed by the China Biodiversity Red List are threatened. Nevertheless, to date, no study has explicitly examined the pattern and processes of extinction and threat in Chinese lizards. In this study, we conducted the first comparative phylogenetic analysis of extinction risk in Chinese lizards. We addressed the following three questions: 1) What is the pattern of extinction and threat in Chinese lizards? 2) Which species traits and extrinsic factors are related to their extinction risk? 3) How can we protect Chinese lizards based on our results? We collected data on ten species traits (body size, clutch size, geographic range size, activity time, reproductive mode, habitat specialization, habitat use, leg development, maximum elevation, and elevation range) and seven extrinsic factors (mean annual precipitation, mean annual temperature, mean annual solar insolation, normalized difference vegetation index (NDVI), human footprint, human population density, and human exploitation). After phylogenetic correction, these variables were used separately and in combination to assess their associations with extinction risk. We found that Chinese lizards with small geographic range, large body size, high habitat specialization, and living in high precipitation areas were vulnerable to extinction. Conservation priority should thus be given to species with the above extinction-prone traits so as to effectively protect Chinese lizards. Preventing future habitat destruction should also be a primary focus of management efforts because species with small range size and high habitat specialization are particularly vulnerable to habitat loss.

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The effects of geographic range size and abundance on extinction during a time of “sluggish”’ evolution

Paleobiology ◽

10.1017/pab.2020.52 ◽

2020 ◽

pp. 1-14

Author(s):

Michelle M. Casey ◽

Erin E. Saupe ◽

Bruce S. Lieberman

Keyword(s):

North American ◽

Fossil Record ◽

Extinction Risk ◽

Geographic Range ◽

Range Size ◽

Late Paleozoic ◽

The North ◽

Geographic Range Size ◽

The Relationship ◽

Habitat Tracking

Abstract Geographic range size and abundance are important determinants of extinction risk in fossil and extant taxa. However, the relationship between these variables and extinction risk has not been tested extensively during evolutionarily “quiescent” times of low extinction and speciation in the fossil record. Here we examine the influence of geographic range size and abundance on extinction risk during the late Paleozoic (Mississippian–Permian), a time of “sluggish” evolution when global rates of origination and extinction were roughly half those of other Paleozoic intervals. Analyses used spatiotemporal occurrences for 164 brachiopod species from the North American midcontinent. We found abundance to be a better predictor of extinction risk than measures of geographic range size. Moreover, species exhibited reductions in abundance before their extinction but did not display contractions in geographic range size. The weak relationship between geographic range size and extinction in this time and place may reflect the relative preponderance of larger-ranged taxa combined with the physiographic conditions of the region that allowed for easy habitat tracking that dampened both extinction and speciation. These conditions led to a prolonged period (19–25 Myr) during which standard macroevolutionary rules did not apply.

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Sexual selection, range size and population size

Ornis Hungarica ◽

10.2478/orhu-2013-0001 ◽

2012 ◽

Vol 20 (1) ◽

pp. 1-25 ◽

Cited By ~ 1

Author(s):

Anders Pape Møller ◽

László Zsolt Garamszegi

Keyword(s):

Sexual Selection ◽

Population Size ◽

Extinction Risk ◽

Range Size ◽

Sexual Dichromatism ◽

Common Descent ◽

Distribution Limits ◽

Western Palaearctic ◽

Linear Contrasts ◽

Average Fitness

Abstract Sexual selection may impose fitness costs on both males and females due to the costs of developing and maintaining exaggerated sexual signals, reducing average fitness in strongly sexually selected species. Such reductions in average fitness could affect local extinction risk and hence distribution range. However, given that both sexually monochromatic and dichromatic species are common and widespread, benefits of sexual selection must be invoked to maintain equilibrium. We tested for differences in breeding range size and population size between monochromatic and dichromatic species of birds in a comparative analysis of species from the Western Palaearctic. In an analysis of standardized linear contrasts of the relationship between sexual dichromatism and range size and population size, respectively, that controlled for similarity among taxa due to common descent, we found no significant relationship. However, when we analyzed carotenoid-based sexual dichromatism sexually dichromatic species had larger distribution areas and higher northernmost distribution limits, but not southernmost distribution limits than sexually monochromatic species. In contrast, melanin-based sexual dichromatism was not significantly associated with range size or population size. Therefore, population density of sexually dichromatic species with carotenoid-based coloration was lower than that of monochromatic species, because dichromatic species had similar population sizes but larger ranges than monochromatic species. These findings suggest that the different physiological roles of pigments associated with sexual dichromatism have effects on total range size of birds.

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Geographic range size and extinction risk assessment in nomadic species

Conservation Biology ◽

10.1111/cobi.12440 ◽

2015 ◽

Vol 29 (3) ◽

pp. 865-876 ◽

Cited By ~ 38

Author(s):

Claire A. Runge ◽

Ayesha Tulloch ◽

Edd Hammill ◽

Hugh P. Possingham ◽

Richard A. Fuller

Keyword(s):

Risk Assessment ◽

Extinction Risk ◽

Geographic Range ◽

Range Size ◽

Geographic Range Size ◽

Extinction Risk Assessment

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Extinction risk is most acute for the world’s largest and smallest vertebrates

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1702078114 ◽

2017 ◽

Vol 114 (40) ◽

pp. 10678-10683 ◽

Cited By ~ 89

Author(s):

William J. Ripple ◽

Christopher Wolf ◽

Thomas M. Newsome ◽

Michael Hoffmann ◽

Aaron J. Wirsing ◽

...

Keyword(s):

Body Mass ◽

Extinction Risk ◽

Anthropogenic Activities ◽

Large Body ◽

Range Size ◽

Bony Fishes ◽

Cartilaginous Fishes ◽

Direct Killing ◽

Negative Relationships ◽

Insight Into

Extinction risk in vertebrates has been linked to large body size, but this putative relationship has only been explored for select taxa, with variable results. Using a newly assembled and taxonomically expansive database, we analyzed the relationships between extinction risk and body mass (27,647 species) and between extinction risk and range size (21,294 species) for vertebrates across six main classes. We found that the probability of being threatened was positively and significantly related to body mass for birds, cartilaginous fishes, and mammals. Bimodal relationships were evident for amphibians, reptiles, and bony fishes. Most importantly, a bimodal relationship was found across all vertebrates such that extinction risk changes around a body mass breakpoint of 0.035 kg, indicating that the lightest and heaviest vertebrates have elevated extinction risk. We also found range size to be an important predictor of the probability of being threatened, with strong negative relationships across nearly all taxa. A review of the drivers of extinction risk revealed that the heaviest vertebrates are most threatened by direct killing by humans. By contrast, the lightest vertebrates are most threatened by habitat loss and modification stemming especially from pollution, agricultural cropping, and logging. Our results offer insight into halting the ongoing wave of vertebrate extinctions by revealing the vulnerability of large and small taxa, and identifying size-specific threats. Moreover, they indicate that, without intervention, anthropogenic activities will soon precipitate a double truncation of the size distribution of the world’s vertebrates, fundamentally reordering the structure of life on our planet.

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Coarse- and fine-scale patterns of distribution and habitat selection places an Amazonian floodplain curassow in double jeopardy

PeerJ ◽

10.7717/peerj.4617 ◽

2018 ◽

Vol 6 ◽

pp. e4617 ◽

Cited By ~ 1

Author(s):

Gabriel A. Leite ◽

Izeni P. Farias ◽

André L. S. Gonçalves ◽

Joseph E. Hawes ◽

Carlos A. Peres

Keyword(s):

Habitat Selection ◽

Home Range ◽

Extinction Risk ◽

Spatial Scales ◽

Habitat Preferences ◽

Open Water ◽

Home Range Size ◽

Range Size ◽

Conservation Strategy ◽

Fine Scale

Patterns of habitat selection are influenced by local productivity, resource availability, and predation risk. Species have taken millions of years to hone the macro- and micro-habitats they occupy, but these may now overlap with contemporary human threats within natural species ranges. Wattled Curassow (Crax globulosa), an endemic galliform species of the western Amazon, is threatened by both hunting and habitat loss, and is restricted to white-water floodplain forests of major Amazonian rivers. In this study conducted along the Juruá River, Amazonas, Brazil, we quantified the ranging ecology and fine-scale patterns of habitat selection of the species. We estimated the home range size of C. globulosa using conventional VHF telemetry. To estimate patterns of habitat selection, we used geo-locations of day ranges to examine the extent and intensity of use across the floodplain, which were then compared to a high-resolution flood map of the study area. We captured two females and one male, which we monitored for 13 months between September 2014 and September 2015. Average home range size was 283 ha, based on the 95% aLoCoH estimator. Wattled Curassows selected areas of prolonged flood pulses (six to eight months/year) and had a consistent tendency to be near open water, usually in close proximity to river banks and lakes, especially during the dry season. Amazonian floodplains are densely settled, and the small portions of floodplain habitat used by Wattled Curassows are both the most accessible to hunters and most vulnerable to deforestation. As a result, the geographic and ecological distribution of Wattled Curassows places them at much higher extinction risk at multiple spatial scales, highlighting the need to consider habitat preferences within their conservation strategy.

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The impact of geographic range, sampling, ecology, and time on extinction risk in the volatile clade Graptoloida

Paleobiology ◽

10.1017/pab.2016.33 ◽

2016 ◽

Vol 43 (1) ◽

pp. 85-113 ◽

Cited By ~ 2

Author(s):

James Boyle ◽

H. David Sheets ◽

Shuang-Ye Wu ◽

Daniel Goldman ◽

Michael J. Melchin ◽

...

Keyword(s):

Ecological Niche ◽

Extinction Risk ◽

Biological Effects ◽

Abiotic Factors ◽

Explanatory Power ◽

Negative Relationship ◽

Geographic Range ◽

Range Size ◽

Age Cohorts ◽

The Impact

AbstractAlthough extinction risk has been found to have a consistent negative relationship with geographic range across wide temporal and taxonomic scales, the effect has been difficult to disentangle from factors such as sampling, ecological niche, or clade. In addition, studies of extinction risk have focused on benthic invertebrates with less work on planktic taxa. We employed a global set of 1114 planktic graptolite species from the Ordovician to lower Devonian to analyze the predictive power of species’ traits and abiotic factors on extinction risk, combining general linear models (GLMs), partial least-squares regression (PLSR), and permutation tests. Factors included measures of geographic range, sampling, and graptolite-specific factors such as clade, biofacies affiliation, shallow water tolerance, and age cohorts split at the base of the Katian and Rhuddanian stages.The percent variance in durations explained varied substantially between taxon subsets from 12% to 45%. Overall commonness, the correlated effects of geographic range and sampling, was the strongest, most consistent factor (12–30% variance explained), with clade and age cohort adding up to 18% and other factors <10%. Surprisingly, geographic range alone contributed little explanatory power (<5%). It is likely that this is a consequence of a nonlinear relationship between geographic range and extinction risk, wherein the largest reductions in extinction risk are gained from moderate expansion of small geographic ranges. Thus, even large differences in range size between graptolite species did not lead to a proportionate difference in extinction risk because of the large average ranges of these species. Finally, we emphasize that the common practice of determining the geographic range of taxa from the union of all occurrences over their duration poses a substantial risk of overestimating the geographic scope of the realized ecological niche and, thus, of further conflating sampling effects on observed duration with the biological effects of range size on extinction risk.

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Correlates of extinction risk in squamate reptiles: the relative importance of biology, geography, threat and range size

Global Ecology and Biogeography ◽

10.1111/geb.12419 ◽

2016 ◽

Vol 25 (4) ◽

pp. 391-405 ◽

Cited By ~ 58

Author(s):

Monika Böhm ◽

Rhiannon Williams ◽

Huw R. Bramhall ◽

Kirsten M. McMillan ◽

Ana D. Davidson ◽

...

Keyword(s):

Extinction Risk ◽

Range Size ◽

Relative Importance ◽

Squamate Reptiles

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Global decline of bumblebees is phylogenetically structured and inversely related to species range size and pathogen incidence

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2017.0204 ◽

2017 ◽

Vol 284 (1859) ◽

pp. 20170204 ◽

Cited By ~ 39

Author(s):

Marina P. Arbetman ◽

Gabriela Gleiser ◽

Carolina L. Morales ◽

Paul Williams ◽

Marcelo A. Aizen

Keyword(s):

Extinction Risk ◽

Phylogenetic Signal ◽

Species Traits ◽

Range Size ◽

Species Extinction ◽

Crithidia Bombi ◽

Internal Parasites ◽

Phylogenetic Perspective ◽

Declining Species ◽

Tongue Length

Conservation biology can profit greatly from incorporating a phylogenetic perspective into analyses of patterns and drivers of species extinction risk. We applied such an approach to analyse patterns of bumblebee ( Bombus ) decline. We assembled a database representing approximately 43% of the circa 260 globally known species, which included species extinction risk assessments following the International Union fo Conservation of Nature Red List categories and criteria, and information on species traits presumably associated with bumblebee decline. We quantified the strength of phylogenetic signal in decline, range size, tongue length and parasite presence. Overall, about one-third of the assessed bumblebees are declining and declining species are not randomly distributed across the Bombus phylogeny. Susceptible species were over-represented in the subgenus Thoracobombus (approx. 64%) and under-represented in the subgenus Pyrobombus (approx. 6%). Phylogenetic logistic regressions revealed that species with small geographical ranges and those in which none of three internal parasites were reported (i.e. Crithidia bombi , Nosema spp. or Locustacarus buchneri ) were particularly vulnerable. Bumblebee evolutionary history will be deeply eroded if most species from threatened clades, particularly those stemming from basal nodes, become finally extinct. The habitat of species with restricted distribution should be protected and the importance of pathogen tolerance/resistance as mechanisms to deal with pathogens needs urgent research.

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Range Size and Extinction Risk in Forest Birds

Conservation Biology ◽

10.1111/j.1523-1739.2007.00798.x ◽

2007 ◽

Vol 22 (1) ◽

pp. 163-171 ◽

Cited By ~ 95

Author(s):

GRANT HARRIS ◽

STUART L. PIMM

Keyword(s):

Extinction Risk ◽

Range Size ◽

Forest Birds

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