Mystery that got science's goat - Barren Island puzzle solved: springs, not special kidneys, sustain animals
New Delhi, Aug. 3: The goats have been sending the men with goatee on a wild goose chase.
Indian and Italian scientists have solved a long-standing — and, in hindsight, “entirely avoidable” — mystery of goats on Barren Island, India’s only active volcano, 135 km east of Port Blair.
Though uninhabited, the 3-km diameter Barren Island is home to bats, crabs, rats, several species of birds and goats which make up the largest mammals on the island.
Historical records suggest that a shipwreck in the Andaman sea more than a century ago may have trapped the goats on the island where thick vegetation and lack of predators — human or otherwise — helped them proliferate. But how these goats have survived and multiplied on the island without any apparent source of fresh water has long puzzled scientists.
It was too much to expect rainfall to sustain the goats through the year. Scientists then began speculating that the goats had over the decades adapted to survive on seawater.
Scientists at the Central Agricultural Research Institute, Port Blair, even suggested that it might be a good idea to rear these animals for meat in drought-prone regions where fresh water is scarce.
A few goats from Barren Island were captured for studies, which were said to have revealed that the seawater intake influenced the dry food intake by the goats. The higher the amount of seawater they consumed, the lower their intake of food.
“Such speculation bugged us,” said Dornadula Chandrasekharam, professor of earth sciences at the Indian Institute of Technology, Powai (in Mumbai). He spent three nights on the island earlier this year along with three other geologists, two from Italy, for the first-ever detailed geological exploration of Barren Island.
Agriculture scientists have in the past tried to study the diet and behaviour of the goats in an attempt to explore possibilities of domestication.
“There were attempts to study the kidneys of the Barren Island goats to find out how they are able to process the high levels of salt from seawater,” Chandrasekharam said.
All for nought, it now turns out.
The three-day Indo-Italian scientific expedition revealed the presence of two freshwater springs on the slopes of the volcano about 100 metres above the sea-level. The researchers observed a herd of six goats grazing on the thick vegetation around the springs.
The freshwater, the geologists said, is just rainwater that has been trapped in underground reservoirs on the slopes of the volcano. “No one looked hard enough,” said Chandrasekharam.
The geologists said more freshwater cold springs are probable on the steep slopes of the volcano.