
A major global conservation effort, aiming to bring to better attention the chronic plight of the world’s amphibian species, was launched at the start of this year. You might have heard of it: the Year of the Frog movement. And, today, a second project aimed at conserving the world’s endangered amphibians launches: the EDGE amphibian project, a website designed by the Zoological Society of London to draw attention to amphibian species that are not just globally endangered, but are also evolutionarily distinct…
As you might have guessed, ‘EDGE’ stands for Evolutionarily Distinct and Globally Endangered. EDGE species have few (or no) close living relatives and are highly distinct in terms of their biology, habits or behaviour. In a talk abstract from March 2007, Jonathan Baillie – head of the ZSL’s Indicators and Assessments Unit – noted that ‘many of the world’s most evolutionarily distinct species are on the edge of extinction, yet they receive little or no conservation attention’. EDGE species are in cases the last surviving members of groups that have had long evolutionary histories, yet they ‘are unfamiliar to both conservationists and the public, and are frequently overlooked by current conservation initiatives’, said Baillie. The loss of EDGE species does not just mean, then, the loss of some of the most interesting species, it also means that we are in danger of losing a disproportionate amount of the planet’s evolutionary history (e.g., Heard & Mooers 2000, Purvis et al. 2000, von Euler 2001). The possibility exists that such losses might greatly reduce the potential for future evolution. Knowledge of a group’s phylogenetic and geological history is therefore an essential tool in setting conservation priorities [purple frog above is Nasikabatrachus sahyadrensis; one of many on the EDGE list].

While some EDGE species – like Giant pandas and Black rhinos – are well studied and relatively familiar, a great many are highly obscure and poorly known. So the plan over the last couple of months – as if you couldn’t guess – has been to build a framework of reference articles on Tet Zoo that essentially introduce the main amphibian lineages and their key traits. With the exception of one article left to do on natatanuran neobatrachians, I managed to get through all anurans (the anuran series has so far consisted of part I, part II, part III, part IV, part V, part VI, and part VII), and of course just recently we did caecilians (part II here) and caudates (part II here) [salamander in adjacent image is the Luristan newt Neurergus kaiseri, an Iranian salamandrid named in 1952; it's also on the EDGE list].
With this framework (virtually) in place, the stage is set for more detailed examinations of specific species and genera, focusing of course on the EDGE amphibian species. Given that I have a particular liking of obscure species, I had to take this on, and indeed you might argue that I had a responsibility to do so, given that virtually nothing non-technical has been written about many of the species concerned. We’re talking about such awesome creatures as the giant salamanders, Australian frogs that have lost their eardrums and communicate by waving their limbs around, miniature Mexican plethodontids, spiny salamanders, olms, the singularly named Togo slippery frog Conraua derooi and Baw Baw frog Philoria frosti… and many others. As of today, lots of information on these species – much of it widely available for the first time – is available at the EDGE amphibian site, and I’m going to be blogging about some of these species over the following weeks and months. You have been warned! Many thanks to EDGE’s Helen Meredith, the EDGE amphibians co-ordinator, for her support on all of this and for getting me involved. A short article by me, essentially similar to this one, can be found here on the EDGE site: bizarrely, I’m not holding an amphibian, but the skull of Dave Hone and Mike Benton’s new rhynchosaur Fodonyx, recently published in Palaeontology. More on that later [white olms Proteus anguinus below; also on the EDGE list].

And for more information here’s Helen Meredith talking about EDGE amphibians…
PS – happy second birthday Tet Zoo! More on that later in the week.
PPS – the EDGE amphibians site is currently having a few teething problems. These will be resolved soon.
Refs – -
Heard, S. B. & Mooers, A. Ø. 2000. Phylogenetically patterned speciation rates and extinction risks change the loss of evolutionary history during extinctions. Proceedings of the Royal Society of London B 267, 613-620.
Purvis, A., Agapow, P.-M., Gittleman, J. L. & Mace, G. M. 2000. Non-random extinction and the loss of evolutionary history. Science 288, 328-330.
von Euler, F. 2001. Selective extinction and rapid loss of evolutionary history in the bird fauna. Proceedings of the Royal Society of London B 268, 127-130.