Poisonous amphibian defenses are linked to higher extinction risk

Date: November 22, 2016

Source: Swansea University

Research published by a Swansea University scientist has found amphibians which have a toxic defense against predators -- such as the iconic poison dart frogs -- have a much higher risk of extinction than species which use other types of defense mechanisms.

The key finding of Dr Kevin Arbuckle's latest study, published in the journal Royal Society Open Science, is that poisonous species are 60% more likely to be threatened than species without chemical defenses.

Amphibians are usually considered the most threatened group of vertebrate animals and are experiencing population declines globally, raising conservation challenges.

The threats to amphibian biodiversity are numerous and include rapid habitat destruction, exploitation, and pollutants entering the environment.

Many characteristics of animals may be linked to contemporary extinction risk. For instance, certain traits are either known or suspected to influence factors such as mortality rates or the ability of populations to recover after declines, and are therefore potential predictors of extinction risk.

The work by Dr Arbuckle, Lecturer in Biosciences (Evolutionary Biology) in the University's College of Science, used amphibians as a model system and tested whether chemical antipredator defense is associated with contemporary extinction rates. This is possible by using conservation status (e.g. 'endangered', 'vulnerable') as a measure of extinction risk in species alive today.

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