Linking Speciation to Extinction: Diversification Raises Contemporary Extinction Risk in Amphibians

Peer reviewed: 
Yes, item is peer reviewed.
Scholarly level: 
Faculty/Staff
Final version published as: 

DA Greenberg & AO Mooers. (2017). Linking speciation to extinction:Diversification raises contemporary extinction risk in amphibians. Evolution Letters 1 (1), 40-48.

Date created: 
2017-05-03
Keywords: 
Amphibia
Diversification
Extinction risk
IUCN
Peripatry
Speciation rate
Species longevity
Abstract: 

Many of the traits associated with elevated rates of speciation, including niche specialization and having small and isolated populations, are similarly linked with an elevated risk of extinction. This suggests that rapidly speciating lineages may also be more extinction prone. Empirical tests of a speciation-extinction correlation are rare because assessing paleontological extinction rates is difficult. However, the modern biodiversity crisis allows us to observe patterns of extinction in real time, and if this hypothesis is true then we would expect young clades that have recently diversified to have high contemporary extinction risk. Here, we examine evolutionary patterns of modern extinction risk across over 300 genera within one of the most threatened vertebrate classes, the Amphibia. Consistent with predictions, rapidly diversifying amphibian clades also had a greater share of threatened species. Curiously, this pattern is not reflected in other tetrapod classes and may reflect a greater propensity to speciate through peripheral isolation in amphibians, which is partly supported by a negative correlation between diversification rate and mean geographic range size. This clustered threat in rapidly diversifying amphibian genera means that protecting a small number of species can achieve large gains in preserving amphibian phylogenetic diversity. Nonindependence between speciation and extinction rates has many consequences for patterns of biodiversity and how we may choose to conserve it.

Language: 
English
Document type: 
Article
Sponsor(s): 
Natural Sciences and Engineering Research Council of Canada (NSERC)
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