Evolution is on wing, says birdman of India’s ‘sky islands’
The word ‘sky island’ (‘sholas’) caught my interest in an article in The Statesman web edition, July 3, a news bit on V.V. Robin’s five-year research in the Western Ghats mountain range, in India’s south-western peninsula. Robin studied songbirds stuck there, not for a few years or decades, but up to five million years! Free birds trapped by geography, for apparently endless time, and evolving in a fate closely linked with humans. I had to know more.
Though I was born in an island in the Indian Ocean, mountains are my lifetime calling, and the Himalayas my very long-term home. There was not much chance of me turning away from an unknown mind puller called ‘sky islands’.
‘Sky islands’, explained scientist V.V Robin in an email to me and for Asia Times readers, is a common term used in different parts of the world. “They are islands in the sky, or habitats existing on mountain-tops that are isolated by different habitats (usually drier) in the valleys”. Sky islands are “high elevation, isolated mountaintops separated from each other by a sea of radically different lowland environments,” he said.
Whether isolated in high mountains or lowly prison cells, long-time solitude can do different things to different living beings, beneficial or painful effects, depending on circumstances, purpose and period. So too with songbirds isolated in sky islands for millions of years. These flying beings are being pushed to further isolation with human encroachment, the roads and dams, coffee plantations and tourist pathways. Yet they do not fly away carrying their songs of solitude, to a different geographic dimension.
With ‘birds’, instant word association would be ‘wings’, ‘flying’ and ‘freedom’, but this species of shortwings do not wish or could not leave their sky islands for thousands, and millions of years. Extinction knocks on their nests.
Shortwings are pocket-sized birds, 25 gms of multi-coloured weight, such as the White-bellied and the Rufous-bellied Shortwings (Brachypteryx albiventris and B. major), living in the shola forests of Western Ghats. “They are about the size of a sparrow and are endemic (found nowhere else in the world),” says ornithologist (bird studier) Robin. [Listen here to the song of the White-bellied Blue Robin (Myiomela albiventris), a mountain bird living in a 1,500 metre high sky island in the Western Ghats.]
How other species evolve offer clues about our own life and times in the planet. All living creatures are part of the same cosmic bio-dance, said retired professor P.L. Dhar of the Institute of Technology, Delhi. At the sub-atomic level of quantum realities, all matter and mind-matter phenomena in the cosmos can be experienced as vibrations, arising and passing, in flux and continual change — every evolving moment. We are inter-connected, in one way or the other.
One such link seems our subliminal response to bird songs, just as one’s moods can swing by time of the day, or season – faraway bells in the twilight, city lights at dusk, drops of sunshine bathing a green garden on a summer afternoon, pitter-patter of rain on a lazy Sunday morning, hearing a blue robin (Luscinia brunnea) while walking on a misty mountain trail…Scientists are studying how bird song influences our thinking and creativity, said a Guardian report, in an inter-connected evolutionary story.
So how much of human history can be gained from studying evolution of these sky island songbirds? “There are parallels in how humans are isolated,” Robin said. “Ethnic communities on different mountains have different dances, languages and cultures. What makes them different is the isolation because of the mountains – the hindered movement between these villages. The same factor — lack of movement — causes differences in birds too.”
In the Himalayas, near the India-Tibet border, remote hamlets still exist with a population of about four families. Like the songbirds in sky islands, these once isolated mountain communities are being slowly swallowed by an encroaching tourism industry. For some, the money and business from trekking operators is a doorway to a life of more prosperity; for others who love the powerful solitude of the silent mountains, it’s a loss of something priceless and timeless, an uncomplicated lifestyle of simplicity, an innocence endangered.
With conservation of endangered species as his aim, Robin explored life of these tiny shortwing birds in sky islands of the Western Ghats – a mountain range running nearly uninterrupted for 1,600 kms (994 miles), until broken by the 40 km Palghat Gap.
In June 2011, Robin presented a co-authored research paper ‘The role of ancient geographical gaps on the evolution of birds on sky islands of the Western Ghats’, at the Evolution Conference in city of Norman, Oklahoma. His research later received funding from the Government of India, the National Geographic Society, Washington D.C, (he is a designated National Geographic Explorer since 2012), and National Centre for Biological Sciences, Bangalore. Robin could now invest years of his life scientifically studying these songbirds of solitude.
V.V Robin’s parent organization National Centre for Biological Sciences (NCBS), Bangalore, is part of the Tata Institute of Fundamental Research based in Mumbai. NCBS mandate is to expand frontiers of biology. Evolution is part of it. If you have seen Steven Spielberg’s Jurassic Park movie series, you might remember that end sequence image: the dinosaur invisibly morphing into a bird flying away into the endless horizon. Robin’s five-year research is part of his 15-year-old continuing journey to understanding how some special songbirds are evolving in their islands in the sky.
“It is like a mystery novel, you can’t wait to figure out the next bit,” said Robin, the scientist birdman. “As in many scientific projects, one project and some answers lead you to many more questions. I started with a project asking where shortwings are found. I had the opportunity and support to be able to ask and answer several other subsequent questions from that initial project. I stayed on because the answers and the biological insights were fascinating”.
Robin and his team studied shortwings in sky islands each about 25 kms (15 miles) to 60 kms (37 miles) wide, across a 600-kms section of the Western Ghats. The Western Ghats, estimated to be older than the Himalayas, is treasured for its rare heritage of rich, unique animal and plant life. In 2012, the United Nations Educational, Scientific and Cultural Organisation (UNESCO) included the Western Ghats as a World Heritage site, and ranked it among the world’s eight “hottest hotspots“of biological diversity. Robin’s sky islands birds are special among the special.
Some sky islands are very small (15 sq km) and naturally isolated, while others are large islands in the clouds (e.g. Nilgiris and Annamalai–Palani), near popular holiday hill stations of Ooty, Kodaikanal and Munnar hills, close to the ancient southern city of Madurai that locals call ‘Athens of the East’.
In his research paper ‘Islands within islands’ (*1), Robin’s team studied how human development disrupts evolution of birds, their genetic connectivity snapped by roads, dams, villages, and agriculture. They tagged over a hundred individual birds in different sky islands. Remarkably, in a time span across five years, they discovered only two instances of song birds flying from one neighboring sky island to another. These songbirds either found paradise in their sky island, or they hated packing bags and traveling.
These reclusive songbirds seem to be turning even more reclusive in their shrinking islands, almost like saying to the encroaching world, “we are special, and we would rather die than lose our special identity.”
A recent study by the National Centre for Biological Sciences, Bangalore, showed how bird species living in shola forest sky islands were connected in the past, but are now disconnected. “Continued fragmentation could lead to small disconnected populations, and possibly extinction,” Robin and his senior colleague Uma Ramakrishnan said: “We hope to use such studies for insights on how best to promote survival of the species in the future.”
Bringing in genetic analyses and computer simulation into conservation biology, Robin’s team studied blood samples of 218 birds. The DNA analysis showed that within these islands of sky forests, due to deforestation, the forest fragments have become even smaller – or islands within islands.
Robin hopes to give these songbirds extended life, save them from extinction. For this, he continues studying how best to restore ancient homelands of the sky island birds. His research hopes to give insights on how climate changes impact a vulnerable species. Shrinking forest lands or depleting natural resources — the sky island songbirds and their human guardians share a similar conflicting algebra of evolution: how to cope and survive endless change, in a life of the routine mundane amid that deep, inner call for freedom.
Raja Murthy is a journalist based in Mumbai, India
1) Research paper ‘Islands within islands: two montane palaeo-endemic birds impacted by recent anthropogenic fragmentation’, by V. V. Robin, Pooja Gupta, Prachi Thatte, and Uma Ramakrishnan; National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bellary Road, Bangalore 560065, India. The paper was published in Molecular Ecology (2015). (doi: 10.1111/mec.13266). http://onlinelibrary.wiley.com/doi/10.1111/mec.13266/abstract
2) Shola Sky Islands. : Why are Shola forests interesting? , V.V.Robin
3) Restoration of Shola forests: Pambar Shola, a success story in conservation, Vattakanal Conservation Trust