SCIENCE

When Frogs Make Love

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An explosion of amphibian research in India

BACK IN 2013, Ramit Singal, along with a companion, got into the habit of exploring their neighbourhood in Manipal late into the night. Carrying a flashlight and with their ears turned up for varied sounds of the night, the two would scour backyards and lonely university parks, turning over dead leaves, stones and plastic wrappers. The two were looking for frogs.

Singal, then only 23 years old and fresh out of engineering college, had recently been introduced to the croaky amphibian’s vast world by researchers. And he had begun to use that information to investigate his surroundings. The idea was to find frogs, check their names, examine their habitat, and move on. “The two of us would talk about how cool it would be to find a new species,” Singal says. “But it was just a joke, you know.”

But among the amphibians they spotted during these nocturnal explorations, they saw one whose description they hadn’t yet come across. Its calls were unusual, almost like the chirping of a cricket—at first they thought it was an insect. And it was exceptionally tiny, just about 0.7 inches long. “It was as big as a thumbnail, maybe even smaller. You could put it on the tip of your thumb,” Singal says. For the next one year, he and his companion pored through books and research papers in journals, but they could not find the name of this particular species.

That’s when they reached out to amphibian researchers. DNA analysis confirmed that this tiny species, hiding in plain sight in the urban landscape of Manipal, was actually new to science. The frog was named Microhyla laterite, its common name being kept Laterite Narrow-mouthed Frog after the laterite soil material where it was discovered. The discovery was announced last year in the journal Plos One.

This, however, wasn’t just beginner’s luck. Since finding the Laterite Narrow-mouthed Frog, Singal— now a conservationist who works at Bird Count India—has been involved in the discovery of another new species, a tiny skittering frog named Euphlyctis karaaval , measuring just 11 cm (also known as skittering frog because of its habit of floating on water and skittering away if disturbed), and the rediscovery of a species considered lost, the Microhyla sholigari (which was first seen in 1997 and scientifically described in a paper published in 2000, but had never been sighted again).

With the Microhyla laterite, Singal was unsure for a long time if he had discovered a new species. It hadn’t been found in a protected area but in an inhospitable urban place, categorised as a wasteland by researchers. People passed by here regularly, there was quarrying and dumping, and a building was coming up nearby. Singal had imagined that if there were any new frog species at all in a populated area like Manipal, scientists would have found them by now. But as Sonali Garg, a Delhi-based amphibian researcher, puts it, “Frogs are dynamic beings.” They can turn up anywhere, hidden deep in a dense forest, camouflaging themselves with the foliage or living underground and emerging only at night to mate; or they show up, even the most exotic and effulgently coloured of them, in unexpected and overlooked spaces such as backyards, dumping grounds and scuzzy drain water.

Researchers no longer have to go just by the way a frog looks or sounds. They can now study its genes to discover if it’s of a species new to science

It isn’t just Singal who is hunting for frogs. Strange new species are being discovered every few months. Across the length and breadth of the country, in remote northeastern jungles and urban coastal towns, hard-nosed scientists and amateur researchers are finding new frogs, rediscovering ‘extinct’ ones, observing new traits and habits, and overturning long-held ideas and misconceptions. Dancing tadpoles, flying frogs, new sexual positions (Kermit Sutra)... their list of newspaper appearances is endless. It is as though an explosion in amphibian research, as one researcher puts it, is taking place.

Garg points out that a lot of this has to do with the fact that prior research on Indian amphibians was so scant. “Most of our knowledge about frogs and their diversity is based on collections made during British rule,” she says. Even naturalists back then mostly collected and examined species close to where they lived or worked. But now researchers are exploring many more places. Technological tools available to them have become more advanced and affordable. They no longer have to go just by the way a frog looks or sounds. They can conduct molecular biology studies, and, looking at a specimen’s genes, discover if it is indeed new to science.

Last year, Garg was part of a study that created a stir in the academic world. Of the over 6,500 known frog species, scientists had until then identified a total of six mating positions. In this Kamasutra of amphibian sex, as their cloacas meet, the male either embraces the female, almost romantically, around her waist (inguinal position), or grabs her by her armpits (axillary position) or by her head (cephalic position); else, he attaches himself to her back with the help of a gluey substance (glued position). If not, the couple sit back-to- back with their faces turned the other way while their cloacas attach themselves (independent position). Or the male frog— exceptionally uncomfortable by human standards—just squats on his partner’s head (head straddle). But Garg and the team she was working with—headed by Dr Sathyabhama Das Biju, who is often referred to as the Frogman of India for discovering over 100 new species of frogs (although a few of these are still to be formally described in journals)—found a seventh position among the Bombay Night Frogs.

As evening turned to darkness in the forests of the Western Ghats, as rivers swelled with the passion of monsoon rains, and the night filled with the mating cries of anticipant male frogs, Garg and the others noticed eager male frogs approaching their partners, clambering atop them, and then—to their surprise— not following the illustrated positions of their risqué rulebook. Instead, the male began to hold nearby branches or leaves to steady himself as the two went about their business. The male then released his semen on to the female’s’ back. And shortly after the female shrugged the male off her back, she began to lay her eggs, which, according to the researchers are probably fertilised by the semen running down her back and hind legs. This revelation— the position was named somewhat blandly the dorsal straddle—created quite a stir. The talkshow host Stephen Colbert even did a piece on the finding, asking “all the tadpoles to cover what will eventually be their eyes” as he went about discussing it.

“Purple Frogs live fairly deep in the ground, but they can judge just when to emerge, when to lay eggs, and the flow of rivers. It’s amazing and yet we know so little about them” - Ashish Thomas, amphibian researcher

Garg has been involved in many other discoveries since. She was part of a team that discovered seven new species of an ancient line of frogs known as the Night Frogs earlier this year. These are so small that they can sit comfortably on a five-rupee coin. And a few weeks ago, she published another study, describing four new species of burrowing frogs belonging to the Fejerverya genus. Prior to this discovery, only one amongst the frogs of this genus, the Rufescent Burrowing Frog, was known to have a burrowing lifestyle. In the past, this frog was considered to be abundantly distributed throughout the Western Ghats and was hence a matter of ‘Least Concern’ vis-a-vis extinction on the International Union for Conservation of Nature’s Red List. But as Garg and her team discovered, earlier researchers had mistakenly classified all Burrowing Frogs as Rufescent in the Western Ghats, when in fact there are several more species, many of them rare.

Amphibian researchers lead tough lives. They lug around heavy equipment—cameras and mikes to record movements and habits—in marshy and slippery terrain in distant forests. Much of this takes place during the monsoons, when exotic frogs emerge from their hidden dwellings to answer the call of their mates. Even so, they have to spend endless nights just waiting, often fruitlessly. Biju and the researchers had to spend some 40 nights in a jungle tracking the intimate moments of love-struck frogs pursuing their partners before they could find concrete proof of a new sexual position. But occasionally, luck will present itself to these hard-nosed researchers in the most unexpected of moments. “We go pursuing one frog mentioned some years ago,” Garg says, “and then we will find something else altogether. That’s how it normally goes with us.” She describes the moment— magical, according to her—when they were walking through forest patches, listening to what they thought were insect calls. “This went on for a long time and when we lifted the leaf litter, we found so many of these incredibly tiny frogs. I had never seen so many tiny night frogs in one place,” she says. The researchers initially thought these amphibians, going by their size and calls, were baby frogs. But they turned out to be, as studies showed, an entirely unknown species.

ANOTHER REASON FOR this boom in amphibian research is the sheer number of amateur researchers now involved in it. As Ashish Thomas, a Delhi-based amphibian researcher claims, there are only a handful of full-time herpetologists (amphibian and reptile researchers) in the country. To discover and document frogs in the Subcontinent, hobbyists without formal scientific qualifications have to join the effort.

This involvement in India, for many amateur researchers, has often come through photography. Caesar Sengupta, a wildlife photographer and the managing director of a diagnostics company in Mumbai, first got introduced to the world of amphibians through Biju and joined his project, The Lost Amphibians of India, which sought to discover frog species that had not been sighted for many years. It was when he first looked through the viewfinder of his camera that Sengupta fell in love with frogs. “All through our childhood we have been taught to disregard frogs, while other animals like tigers are extolled,” Sengupta says. “But the frog is a really beautiful creature. And it is as important as any species.” Sengupta now conducts wildlife photography workshops and expeditions around the frog. And for his efforts, Biju last year named a new frog species after him (Hylarana caesari). There are several such groups now. There are frog walks in Bengaluru. A cellphone app, Frog Find, lists frog species’ photos, recordings of their calling patterns, and information on their habitat. Amateur researchers, using this app, can report sightings, hopefully spot new species, and chat with frog researchers. A blogger who runs a popular travel and wildlife blog called Girl Gone Birdzz, uses hashtags such as #FrogFact and #NotJustFrogs to discuss these amphibians. Singal has been recording frog calls, and recently, along with some researchers, even came out with a CD of various frog calls.

“Frogs have become incredibly popular with wildlife photographers,” Sengupta says. “People are realising that they are very beautiful creatures to photograph.”

Ashish Thomas has spent several years studying one of the most elusive of frogs in the world, funded by the Rufford Foundation which backs nature conservation projects. The Indian Purple Frog is an unusual bloated species that lives underground and was discovered in 2003 by Biju, after he was tipped off by a friend about a creature that “looks like a tortoise but I think is a frog”. It is now considered an exceptionally important frog species in evolutionary research. Its closest relatives are located in the archipelago of Seychelles, and it is believed to have split from the Seychellean frogs at least 130 million years ago. “It is older than the Himalayas, before India became a part of Asia,” Thomas says.

A lot about the Purple Frog is still unknown to scholars. But Thomas, who had no interest in amphibians until a few years earlier, is beginning to appreciate the world of frogs as he pursues its most elusive member. “They live fairly deep in the ground, but they can judge just when to emerge, just when to lay eggs, and judge the flow of rivers. It’s amazing really and yet we know so little about it,” he says. But this frog that has survived for around 130 million years, he is beginning to learn, is gradually being threatened, not just because of habitat loss, but also—as he discovered last year— by villagers consuming its tadpoles as food.

The threat of extinction looms across amphibian research in India even as it has begun to flourish. As researchers point out, despite the huge numbers of new species being discovered, time is running out, and many frog species will simply vanish before they are found and named.

To several researchers, meanwhile, there are small joys to take solace in. Whenever Sengupta travels and chances upon a Hylarana caesari specimen, he cannot help but tell his companions who the frog is named after.

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