The frog, the legendary leaper, is nature’s original connection between fish and all living vertebrates. Frogs were also the first animals to possess a genuine voice, tongue and ear drum—since their ‘baptism’ on the living planet, over 250 million years ago. That they are considered the least harmful to human beings—because, the swampy, low-lying area inhabitants cause no penury of any kind to the farmer—is one thing. On the other, they do not also rob us of our grains, or fruits.
The role of frogs as agriculture’s most trusted friend and also nature’s pest-controlling agents is well established. This isn’t all. Frogs are a boon to medicine—they possess natural pharmaceutical agents. They have been used to formulate a painkiller more potent and safe than any other produced, till now. Epibatidine, the constituent in point, is supposedly 200 times more effective than morphine. Yet another element, bradykinin, a peptide, is evidenced to ease high blood pressure. Dermaseptin, likewise, is hailed for its ability to treat antibiotic-resistant infections, just as much as magainin, an antimicrobial peptide, is touted in certain quarters as a potent cure for diabetic foot ulcer, a difficult-to-treat condition. The list is long; it is also good news not only for the medical world, but also patients.
Yet, the paradox is not everything is hunky-dory for the amphibian on its survival front. There has been, as research and scientific evidence highlights, an appallingly alarming decline of amphibious species, across the world. Some examples—the gastric-brooding frog [Rheobatrachus] in Australia, the rice puddle frog in Japan and the golden toad [Bufo periglenes] in Costa Rica. While the Indian Bull frog [Rana tigrina], is now on the protected list, the Yosemite toad species and mountain yellow-legged [Rana muscosa] frogs are almost extinct in the Sierra High County of California, US, once their favourite preserve. Not only that. The illustrious leopard frog populace has dwindled progressively, while the giant tree frog [Hyla vasta] species is also quickly disappearing from its native colony in Haiti.
Amphibians are monitors of our environment. They are vulnerable to several influences—this is simply because they are not protected by scales as fish are. They take in oxygen through their skin, which also absorbs noxious gases and other fluids without ado. As a result, and also because of their delicate lifecycle, through which they are exposed to their surroundings in ways human beings aren’t—for instance, chemical abuse during the tadpole stage—most amphibians seem to be specifically susceptible and ‘at risk’ to a host of environmental poisons.
Research attests that there is one major reason for the rapid depletion of frogs. It is their habitat destruction. Picture this—massive logging operations and agriculture, to pick just two cases in point. The duo in tandem is wiping out the earth’s richest amphibian range in the rain-forests of South America, Malaysia, Indonesia and Africa. Add to it, acid rain and snow, more so the latter whose timing coincides with the spawning of salamanders in Europe, not to speak of widespread industrialisation, automobile pollution, pesticides, game fish—fish that devour amphibians—and, drought, and you have a dreadful portrait for the gloomy amphibious vanishing act. Yet another plausible aetiology, or cause, for the poignant trend, is pure common sense—no trees, no tree frogs.
Interestingly, human penchant for frogs’ legs is another contributory factor, with India, Malaysia and Indonesia, among others, exporting enormous quantities of frogs for gourmet consumption. Though the Indian government banned the export of frogs’ legs, several years ago, the ‘froggy’ business allegedly flourishes under cover. It is also obvious that the hapless animals’ use in schools, colleges, labs etc., has caused incalculable damage to the animal’s existence, notwithstanding a blanket ban on laboratory and other experiments. The simple fact is several families eke out a living by ‘catching’ frogs in the countryside and providing them for zoology lessons, also dissection, in academic and other institutions, among others.
There is a dim light at the beginning of the tunnel—although the only silver-lining in the dark cloud is that some amphibians that favour land are managing to hold fort, by the ‘skin of their sheath,’ as they can bear, or cope, with certain amounts of acidity. Zoologists, however, argue that they are exceptions to a rather dismal prognosis. New studies suggest that out of the 3,000-odd known species of amphibians in the world, a handful of them may be doing okay. The inference is portentously prophetic.
There is more to frogs than what we often deduce. If frogs vanish, a variety of animals will feel the impact right away. Frogs eat a large number of insects. They are, in turn, a favoured prey for several predators—birds, reptiles and mammals. The frog is also an ecological touchstone. A requiem to its existence could set a number of [in]adequately understood dominoes tumbling. Yet, there is no stopping—the loss of frogs seems to be more widespread than thought. A number of frog species native to the Brazilian rainforests, for instance, have also dwindled. In the UK and Cameroon, the haven of the common toad [Bufo bufo] and Goliath frog [Conraua goliath] respectively, the endangered tag is catching up fast.
Amphibians play a fundamental role in natural balance—they outnumber birds and eat more insects than birds do. What’s more, tadpoles are known to ‘eat’ vegetations that might, otherwise, block streams. As a PBS documentary explored with dramatic and also alarming augury that more than a third of all amphibians have already been lost, and more are disappearing every day. This is an environmental crisis unfolding around the globe—from Australia and elsewhere to North and South America.
Where the croak of frogs once filled the air, one only hears silence. Habitat loss, toxic waste and a human population that has more than doubled in the past 50 years have set the stage for frogs’ diminished numbers. In addition, a fungus called chytrid is reported to be the key culprit. What’s more—the spread of the fungus can’t be clogged. Chytrid continues to move quickly, extinguishing entire frog populations in a matter of months.
It is gratifying that a handful of intrepid scientists have taken the lead, including drastic measures to counter the slide—such as evacuating frogs from the wild and ‘baby-sitting’ them in a sterile environment. Yes, the paradigm change may have come in just a little too late, albeit the El Valle Amphibian Conservation Center in Central Panama, is a ‘game changer’—it houses 58 species of frogs, including the rare golden frog [Atelopus zeteki], which no longer exists in the wild. The other big hope is the Burbayar Forest, the only chytrid-free area left in Panama, a ‘frog thriving’ environment. It buzzes with healthy, ‘untouched’ amphibious life.
Frogs may seem small and too insignificant, but their bodies may hold the key to important new discoveries in medical research, as already cited. Medical science is unravelling a host of chemical compounds found in frogs’ skins that can be used not only to quell pain and block infections, but also as a potent HIV treatment. A research team has found 75 different antimicrobial peptides on the skin of the common European brown frog [Rana temporaria]. The peptides are believed to be therapeutically useful for the prevention of pathogenic and antibiotic-resistant bacterial strains. Yet, the writing on the wall is ominous—the discovery of future medical miracles could be dramatically slipping away with the swansong of numerous amphibious species across the globe.
It would also not be theatrical, in the context, to underline the fact that our health and that of frogs is unmistakably intertwined. The impact on the world’s ecosystems, as a result, is great. Frogs are ensconced right in the middle of the food chain, and without them, other creatures will be disappearing too. The most disheartening thing is we are only beginning to understand what life may be like without them. This underscores the scientific race that is currently on to stem the tide, before the next frog crosses the thin, green safety line.
To state the obvious—the most significant catchphrase of our times is ‘threatened by extinction.’ Frogs are no exception, after having thrived on earth for ages, just like other hapless species that may now be extinct. The tragic part is that the true groundswell of concern for their impending doom, or plight, is yet to gain momentum on a global scale, like other environmental issues. If this is not just the tip of the iceberg, but a ‘Titanic’ leapfrog to disaster, what is?
Go figure.
— First published in Madras Courier
