New Delhi: Pretty much like the Indian economy, the number of new frog species in the country appears to have boomed.
Controversial find: The giant wrinkled frog is one of the biggest to be discovered in India
In the seven years ended 2007, 18 new species have been discovered from the Western Ghats — the largest find in any decade in the last 100 years.
This brings the total number of frog species in India to about 230. More than half of these have been discovered in the Western Ghats, with nearly one-fifth of them being discovered since 1995.
And this at a time when world over organizations such as the Global Amphibian Assessment and the World Conservation Union have raised alarm that frogs, along with other amphibians, have recorded massive elimination of species and a steep decline in numbers since the 1950s because of a host of factors, ranging from adverse effects of climate change to a deadly fungus.
Amphibians, such as frogs, are a crucial indicator of the ecological health of a system. Because amphibians have highly permeable skin and spend a portion of their life in water and on land, they are sensitive to environmental change.
“Moreover, they come somewhere in the middle of the food chain and their presence in sufficient numbers indicates that other life forms such as snakes and insects are also present in good numbers,” said A.J. Philips, a zoologist at the Delhi University.
Small wonder: India’s smallest known frog yet, Nyctibatrachus minimus, was discovered last October by S.D. Biju, an amphibian expert at the Delhi University, in the Waynad district of Kerala
However, the spurt in discovery of new species of frogs in the Western Ghats has encountered a controversy, following a dispute over the veracity of one of the claims. It has, in its wake, raised questions on the process and the ethics, particularly with respect to the practice of killing the frogs to preserve a specimen associated with the discovery of a new species. Ecologists argue that these issues need to be resolved immediately because the next few years are expected to see another surge in discovery of new species of frogs.
Crawling through marshes and getting lucky enough to hit upon a frog that you think is new to science is just the first step. The researcher must then publish his findings in a peer-reviewed science journal, proving how the frog is different from discovered ones. These journals send all research papers to an independent set of experts whose names are kept secret and they will take a call on whether a paper is worthy of publication.
Museums or repositories that stock a specimen give researchers depositing type specimens a registration number and leading journals insist that this number be quoted.
In 2001, S.V. Krishnamurthy, a professor at the Kuvempu University in Karnataka, described what he thought was a new frog retrieved from the Kudremukh National Park in the Western Ghats.
Called the giant wrinkled frog, it was, by far, one of the biggest among its species, Krishnamurthy wrote in Current Science, one of India’s most respected science journals.
Established practice requires that all animal species must have a Latin scientific name, according to the Code, which is a tome of rules accepted by taxonomists the world over.
The Code is prepared by the International Commission on Zoological Nomenclature, or ICZN, a 117-year-old private trust based out of the Natural History Museum in London, whose main job is to resolve disputes regarding the naming of animal species.
Going by the Code, Krishnamurthy formally named his frog in Latin as Nyctibatrachus hussaini. In his paper, Krishnamurthy said the research was part of a department of science and technology study under a Union government-sponsored project, and it was called hussaini in honour of S. Hussain, a noted ecologist with the Biodiversity Initiative Trust, Mangalore—a non-governmental organization.
However, last October, K.P. Dinesh and C. Radhakrishnan, scientists from the Zoological Survey of India, or ZSI, the government body that enumerates wildlife in India, claimed that N. hussaini was an invalid name, as Krishnamurthy didn’t deposit a type specimen in a nationally accredited depository or museum — a stringent requirement of the Code.
“Type specimens are like reference samples,” said Karthik Vasudevan, an amphibian expert with the Wildlife Institute of India, “and the whole point of depositing it in a national depository is that anybody who thinks he has found a similar looking species can compare it with existing samples, and not blindly claim discovery of a new species.”
“Though Krishnamurthy claims to have deposited at the range forest office, which is not a national depository anyway, we couldn’t find it over there,” says Radhakrishnan.
Says Manjunath Chauhan, the district officer under whose jurisdiction the Kudremukh National Park falls: “We don’t have any records of such a sample, and there is no receipt or proof that such a sample was deposited in the office. Anyway, researchers discovering species must be putting samples in a nationally certified depository, or university or museum.”
Coincidentally, Radhakrishnan and Dinesh discovered the same frog, deposited it at the Western Ghat Research Station in Calicut, a national depository, and renamed the same frog N. karnatakaenisis.
“We don’t want to take credit from Krishnamurthy, but if the frog’s name isn’t changed it will lead to a lot of confusion,” said Radhakrishnan.
The matter has become more complicated because different authorities have different names for the same frog in their database.
For instance, the World Conservation Union, the largest international conservation network in the word, lists the frog as N. hussaini, whereas the American Museum of Natural History, which has the largest database of animal species in the world, lists it as N. karnatakaenisis.
Krishnamurthy, however, refutes the challenge to his claim.
“I don’t know of any other paper about N. hussaini except for mine,” he said, but refused to answer any other questions. He also didn’t return several other calls made to his cellphone.
Prior to 2000, the Code didn’t insist that specimens be deposited.
“But it went from being an additional to a requirement after there were a whole lot of species being discovered and some of them were so similar that you needed physical samples to correctly distinguish between them,” said Darrel Frost, who is the curator at the division of vertebrate zoology at the American Museum of Natural History.
The controversy has got more curious because another scientist has endorsed Krishanmurthy’s claim.
“I first collected this frog in 1990,” said Ranjit Daniels, an ecologist and president of Care Earth, an organization that works on conservation issues. “I thought it was N. humayani (another member of the species), and sent it to the Bombay Natural History Society for comparison. They registered it as N. major (yet another of the same species).”
However, a senior scientist at ZSI, Chennai, had told him it wasn’t N. major, said Daniels, “and as I am an ecologist more than a taxonomist and didn’t pursue the matter further.”
Ten years later, Krishnamurthy showed Daniels photographs of his find. Thereafter, Daniels advised Krishnamurthy to publish his findings in Current Science, because only if you describe your findings do you get credit for discovering a species. “In fact, I was the one who forwarded his paper to Current Science,” said Daniels, who claims to have reviewed several papers for the journal.
The ethics challenge
The controversy has taken a curious turn with some ecologists challenging the practice of killing the frog to preserve a sample and instead have made a case that high resolution pictures should suffice as evidence.
“The ICZN asks for a whole lot of samples. So a lot of researchers are killing frogs by the dozen. This defeats the whole purpose of conservation,” said Daniels. The number of different species located in an area is a crucial measure of what constitutes a biodiversity hotspot, said N.A. Aravind, an amphibian researcher with the Ashoka Trust for Research and Ecology, an organization involved with bio-conservation issues.
“The Western Ghats is a biodiversity hotspot and by virtue of being one, a lot of international agencies are funding conservation research programmes in the region. In fact, it’s the availability of such funds over the last two decades, that is also encouraging researchers to step in the fields and look for frogs,” he added.
However, Frost says that photographs as proof of a discovery are defensible, only if a species is critically endangered.
“But, most species being discovered now are present in large populations, so unless it’s some rare bird or a primate, it’s best and necessary to have samples.”
S.D. Biju, an ecologist at the Delhi University, who recently described the smallest frog out of India, said that while type specimens are an absolute necessity, “there are too many frogs waiting to be described from the Western Ghats, for scientists to be arguing about one.” He says that he himself is soon set to describe a “a huge collection of frog species.”
At the same time, the controversy over the claim has also put the spotlight on the practice followed by Current Science.
In their paper, Radhakrishnan and Dinesh say, “..the reviewers of the paper in the journal, as qualified taxonomists of amphibians are also equally responsible for overlooking the error.”
According to them, the reviewers should have ensured that a sample, following the ICZN Code, was deposited at a nationally recognized repository. But N.V. Joshi, the associate editor of Current Science and also professor at the Indian Institute of Science, Bangalore, doesn’t think there’s any problem.
He says that being an interdisciplinary journal, Current Science doesn’t have the same set of rules that dedicated taxonomy journals follow. “Some international bodies require that to describe the molecular structure of an organism, a researcher must deposit a sample somewhere. We don’t insist on that.”
At the same time, he let on that “in the future, we will certainly ask our reviewers to consider the importance of mentioning registration numbers, when describing species.”
Complicating the future
Scientists such as Vasudevan say that though the Ghats are a treasure trove of undiscovered species, the actual number of frogs may be inflated because lots of researchers were justifying minor differences within frog species as grounds for describing new species.
“Describing a species is hard work. If many frogs look similar to each other, you must compare large number of samples and ensure that these are sufficiently different from each other,” Vasudevan said.
In 2002, scientists from Sri Lanka described about 100 new frog species in Science, “but we analysed that data and found that most of them were on very minor grounds,” said Vasudevan.
He had published a detailed paper in Current Science questioning the claim.
Traditionally, species are differentiated on the basis of the size, weight, spacing between the webs on their feet, and eyes.
However, the introduction of new techniques such as molecular marking to identify a species is expected to make the process of claims on new species more challenging as it could reject some of the existing claims or may well end up boosting the number of species that have been discovered.
“That’s a very popular technique nowadays,” said Karthik Shanker, an ecologist at the Indian Institute of Science, Bangalore, “but you need a big database of various DNA to use that as a viable ground for comparison. 98% of a chimpanzee and human genes are the same, but that won’t make them members of the same species.”