The Frog Purana

In 2003, Biju and his team had given science another wonderful story of survival from the Jurassic age. The purple frog (Nasikabatrachus sahyadrensis), which he discovered in the Western Ghats near Idukki in Kerala, also shared space with dinosaurs and survived through four mass extinctions. Amphibians were the first creatures to venture on land, having evolved from fish. These early amphibians are the progenitors to all contemporary species, including reptiles, mammals and birds. They are the key to unlocking nature’s big secrets, an incredible cache of information and survival skills that puts human achievements to shame. Today, there are three overarching families of amphibians: salamanders, frogs and caecilians.

For 30 years, Biju has been scouring India’s forests, searching for the secrets that lie hidden, for species that could connect us to the advent of life, for a little squeak in time’s silent aeonic theatre. “I go to see the forests. I watch the rains. I wait. I listen. If the frogs don’t croak, that is also a question to be asked. It is not necessary that you will see or find something new. Nature will come to you. For me, spending a night time in a forest listening to the call of the frogs is eternally fascinating,” says Biju, sitting in the systematics lab of the Centre for Environment Studies in Delhi University—flanked on all sides by formaldehyde bottles of creepies and crawlies.

(From top left) Chalazodes bubble-nest frog; chikila egg; polypedates bijui; India’s tiniest frog, the Nightfrog, is 10 mm long

For a man who, as he says, could have easily settled for a life of comfort as a professor with a steady paycheque handing out notes for rote learning, Biju’s has been a refreshingly hands-on career. Over the last two decades, he has discovered and documented more than 150 species of amphibians, one of which, the Biju’s Tree Frog (Polypedates bijui), is named after him. He has been published on 70 (of the 150) species, eight genera and two families. Each (re-)discovery of a species shifts the frontiers of science a wee bit more; Biju trudges along the edges of this betweenspace, where life is born or perishes in a wink of an eye.

Bittu Sehgal, editor of Sanctuary magazine says, “Biju’s research and surveys, using students, communities and scientists, prove beyond doubt that half of all frogs face extinction. Apart from pure natural history insights, his team’s consistent discovery of amphibian species suggests that all is not lost in the Indian subcontinent. Our wetlands hold the key to human survival in an era of climate change.” The web of life has a billion unseen bits that keep the macrosystem running, Biju’s colleague Aniruddha Mookherjee says, adding it’s people like Biju who can make the government see how significant their point of view is.

For a person who has introduced us to such trans-epochal sagas of evolution and extinction, Biju’s had been a down-to-earth start to life. He received his schooling at a government institution in Kadakkal, located near the Western Ghats in Kerala’s Kollam district. He recalls, “I have no memory of school life at all. For me, school was secondary. Helping my parents milk the cow and taking the cattle to graze is my main memory. There, I sat in the forest wondering at its might and the wonders it hid.” Indeed, one might say that it is to such pastoral ruminations that science today owes so much. Over the decades that followed, Biju would revisit and play out this childhood fascination time and again as he dug out the secrets that the forests once hid from him. He finds the night the most fascinating time of day. In its piercing silence, he can hear the frogs playing out their mating games. It was one such cat-like catcall that allowed him to discover the meowing night frog in the Western Ghats which he named Nyctibatrachus poocha (poocha meaning cat in Malayalam).

Biju’s purple frog and the chikilidae (a variety of caecilian) may have survived over several millennia because they are burrowing amphibians and live underground, cushioned by the soil. The chikilidae of the Garo hills, whose ancestors would have been trampled underfoot by the dinosaurs, can burrow through the toughest soil using their hard skull and can vanish at the slightest vibration, a valuable survival skill. As Biju says, “It’s like a rocket. If you miss it the first try, you will never catch it again.”

The purple frog, the first frog family to be discovered since 1926, also burrows with its snout nose, lives underground and sucks up food. The male only comes overground to mate. This purple frog and the chikilidae both lived in the southern supercontinent Gondwana, of which India formed the eastern end. When tectonic shifts forced the continents to split and drift apart about 120 million years ago, such hitherto proximate species drifted away too.

Safe in their hidden homes, they survived for millennia, staying unseen even to science’s prying eyes. For many years, locals in the Garo hills thought the chikilidae to be small snakes. Today, 32 per cent of amphibians face extinction. Biju and the Lost Amphibians of India initiative are working to conserve them, but the large-scale destruction of forests are driving most to extinction, especially in the Northeast. Amphibians make up the highest number of critically endangered vertebrates in India.

It has been four long months of classwork for Biju. He says, “In two months, I will start again: this time in the forests of Central India. People ask, ‘What will you find there?’ But you have to work against the common thinking. I have to go there and see.” Who knows, somewhere in the darkness of the forest, he might hear another cry, a squeak, or a croak that will get his adrenaline flowing again. Science may have to make room for yet another new species... and then, to pull it back from extinction.