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Are we in the midst of the sixth mass extinction? A view from the world of amphibians

Identifier

028104

Type of Spiritual Experience

None

Background

A description of the experience

Published online 2008 Aug 11. doi: 10.1073/pnas.0801921105
PMCID: PMC2556420
PMID: 18695221
Colloquium Paper
Are we in the midst of the sixth mass extinction? A view from the world of amphibians
David B. Wake*† and Vance T. Vredenburg*‡

Abstract
Many scientists argue that we are either entering or in the midst of the sixth great mass extinction.

Intense human pressure, both direct and indirect, is having profound effects on natural environments.

The amphibians—frogs, salamanders, and caecilians—may be the only major group currently at risk globally. A detailed worldwide assessment and subsequent updates show that one-third or more of the 6,300 species are threatened with extinction. This trend is likely to accelerate because most amphibians occur in the tropics and have small geographic ranges that make them susceptible to extinction.

The increasing pressure from habitat destruction and climate change is likely to have major impacts on narrowly adapted and distributed species. We show that salamanders on tropical mountains are particularly at risk.

A new and significant threat to amphibians is a virulent, emerging infectious disease, chytridiomycosis, which appears to be globally distributed, and its effects may be exacerbated by global warming. This disease, which is caused by a fungal pathogen and implicated in serious declines and extinctions of >200 species of amphibians, poses the greatest threat to biodiversity of any known disease.

Our data for frogs in the Sierra Nevada of California show that the fungus is having a devastating impact on native species, already weakened by the effects of pollution and introduced predators. A general message from amphibians is that we may have little time to stave off a potential mass extinction.

The source of the experience

PubMed

Concepts, symbols and science items

Concepts

Ages of Man

Symbols

Science Items

Mass Extinction

Activities and commonsteps

Activities

Commonsteps

References