Perhaps because I am fond of frogs - I lived for 20 years in a house called "The Frogs" in a south Indian village - and because all who live in tropical India are acutely aware of the cacophony of the frog chorus which accompanies the first heavy rains of the monsoon, I seized this volume with more than usual eagerness and delight. I was not disappointed, and I learned much. As the authors rightly say of their book: "This constellation of topics will be full of surprises, for the animals described here have been moulded in remarkable ways by the process of natural selection, and the rapidly advancing front of amphibian biology is creating a cascade of discoveries."
So it is all the more frustrating to find that the authors seems to have gone out of their way to make reading the book as difficult as possible. Is it really necessary to break up sentences right in the middle with learned academic references? The line illustrations are excellent, utterly delightful, but the photography, all in black and white whereas the subject matter surely cries out for colour, is muddy and amateurish, with distracting, fussy backgrounds. Muddy environments are where you expect to find amphibians, but they could surely have been subdued for purposes of clarity in the photography. Muddyness is as offensive to photographers as it is agreeable to amphibians. The photograph of the remarkable Suriman toad, which rears its young in pockets on the skin of its back, is an example. That is a very bad photograph of a very dead toad.
But having exorcised those problems we are left with an excellent, informative book full of wonders and delights. I knew that the giant frog of tropical West African rain forests goes up to seven pounds, but I had not known of the smallest species, no bigger than a fingernail. The book also offers us the obvious but perhaps not glaringly apparent lesson that the amphibians are a vital link in the food chain from, for example, the invertebrates to many birds and snakes. Herons, many egrets, snakes like the keelbacks of tropical rice-fields would by themselves be unable to exploit the prodigious protein food source provided by insects such as mosquitoes and their larvae: frogs and other amphibians eat such invertebrates and are themselves a food source for the birds and reptiles.
It is both amusing and alarming to learn of a giant tropical frog aggressive enough to bite even lions and humans that trespass within its breeding grounds. In a lifetime working with animals of all kinds I have been bitten countless times by a wide variety of species - from the cat family (but not, happily, the larger ones) through to reptiles (but not, happily, the venomous ones) and even bats, - but not so far by a frog. I fancy any amphibian bold enough to bite a lion would earn everyone's profound respect.
Venomous animals are generally thought to be confined to snakes, though in fact only a comparatively few species are dangerously venomous to man, so the venoms of the amphibians, as well as marine animals, are overlooked.
Here again, the authors astonish us: we are well aware of the "poison arrow frogs" whose poison is used by Amazonian tribes, but not that there are so many species of them, nor that the poison of certain newts is biochemically almost identical to that of the puffer fish and other deadly marine animals. This poison, known as tetrodotoxin or TTX, is the most lethal non-protein substance known.
Harry Miller is a fellow, Zoological Society, and an award-winning photographer.
A Natural History of Amphibians
Author - Robert C. Stebbins and Nathan W. Cohen
ISBN - 0 691 03281 5
Publisher - Princeton University Press
Price - £19.95
Pages - 316