For centuries, Mumbai's Parsis have brought their dead to the Towers of Silence to be devoured by vultures, a traditional form of "burial" the community insists is hygienic, efficient and in keeping with their faith. Yet these days, there are very few of the carrion-eaters to be seen.
With Asia's vultures having been drastically reduced by the widespread use of toxic pesticides, the Parsis have been forced to erect solar concentrators – essentially large magnifying lenses – to help turn the corpses into dust. "There are not many vultures," said Cyrus Siganporia, a retired engineer who helps at the peaceful, secluded site on the city's Malabar Hill where peacocks strut and birds sing. "They come sometimes, not often. 'Sometimes' is the word."
But while India's Parsis are suffering from a shortage of vultures they are also facing a much more pressing problem, a shortage of themselves. Never vast in scale, almost everyone agrees that the community's numbers are now falling perilously low. A 1940 census put the total of Parsis at 114,890 but a similar count in 2001 discovered the community that follows one of the world's oldest religions, and which included the late Freddie Mercury, the industrialist Ratan Tata and the writer Rohinton Mistry among its members, may now number as few as 69,000. Almost all live in and around Mumbai.
The falling numbers have created an increasingly heated debate within the Parsi community on how best to tackle the problem. The debate, which has led to name-calling and accusations of racism and sexism between the traditionalists and the reformists, has included religious, social and legal issues.
And the arguments are only likely to get hotter and more aggressive. Within months, the Parsis of Mumbai will for the first time be able to vote directly to elect the members of their ruling council, or panchayat. The new council will play a crucial role in helping decide what direction the Parsi community takes in coming years, and as the election date gets nearer both sides are becoming more outspoken. "It's quite aggressive," said Mehernaaz Sam Wadia, a 28-year-old lawyer who, with her brother, runs a blog dedicated to Parsi issues. "Things are heated between certain people."
Parsis are Zoroastrians, followers of the prophet Zarathustra and ethnic descendants of Persians who took refuge in India more than 1,300 years ago when Muslims overthrew the Sassanid Empire. Believers in the god Ahura Mazda, Zoroastrians, who number only about 200,000 worldwide, with the rest living mainly in Iran, worship in front of symbols of the sun or fire. They believe active participation in good deeds and works helps keep the universe's chaos at bay. They believe, too, in the purity of the elements, hence their tradition of neither burying nor cremating the dead but in laying out their bodies to be cleaned to the bone by carrion-eaters.
Although they have always been small in number, India's Parsis have been unusually successful. In addition to the late lead singer of Queen, whose real name was Farrokh Bulsara and who attended St Peter's boarding school in Mumbai, many have held senior positions within government, business and the military. The Godrej industrialist family – well known for its philanthropic projects in and around Mumbai – are Parsis, as was Field Marshal Sam Manekshaw, the former chief of staff of the Indian Army, who died this week.
More prosperous and better educated than most Indians, Parsis typically marry late and have few children. But such habits have helped create the Parsis' numbers problem. Despite initiatives such as paying 1,000 rupees (£12.50) a month to any Parsi family that has a third child, the death rate in Mumbai stands at about 1,000 Parsis a year; there are only about 200 new births.
Jehangir Patel, editor of Parsiana magazine, lists every month the community's births, deaths and marriages. "There has been no direction on how to deal with this problem," he said in his office, in a yellowing, 100-year-old building in the south of Mumbai that once housed a Parsi hospital. "People meet in private but nothing gets further than that. If the election happens, I think the trustees coming in with a mandate would be in a position to give leadership."
The issues to be highlighted in the election relate directly to the Parsis' population problem. A key issue is that of conversion. Traditionalists say it is impossible for anyone born outside of the Parsi community to join the religion. They also insist that while the children of a Parsi man who marries outside the religion are recognised as Parsis, that does not apply to a Parsi woman who marries outside of the community. The reformists want to open the doors.
Among those pushing for a more liberal, tolerant approach are the brothers Kerssie and Vispy Wadia, two Mumbai-based businessmen who are building a so-called fire temple that will be open to the spouses of Parsis who have married outside the fold. The brothers insist their opponents are less interested in religion than they are with the ethnic purity of the Parsi community.
"They have turned our great religion into a small club of just 69,000 people," said Kerssie Wadia, who with his brother set up the Association for Revival of Zoroastrianism (ARZ). "There is a motive for our action and that is to save our religion in India. I want my religion to survive in India. We believe that Zoroastrianism should survive even if Parsis don't."
The ARZ has already been donated land for the new temple and the Wadias said 18 Parsi priests have agreed to become part of the project. The brothers say 120 spouses who have recently married Parsis in Mumbai will be welcomed at the temple.
Asked about allegations that they are changing the foundations of their religion, Vispy Wadia said: "We are more orthodox than [those who oppose us]. We follow all the rituals in their totality. We are trying to bring it back to what it was before they made it into a racist religion. To us, the religion is more important than the question of race but to our opponents it's the other way around. It has become ingrained with Parsi psychology."
If the Wadias represent one end of the spectrum, the other is occupied by people such as Khojeste Mistree, a chartered accountant and scholar who established the Zoroastrian Studies institute. Mr Mistree is one of the most outspoken members of the community and says he is a "voice in the wilderness". Opposed to conversion and a defender of the tradition that recognises only the children of male Parsis who marry outside the community, he even questions the very claim that the Parsis' numbers are tumbling. He also defends the traditional "sky burials" at the Towers of Silence, which is strictly off-limits to non-Parsis and which some members of the community have rejected, opting for cremation instead.
"I think what we are seeing is redistribution of [Parsis] around the world," he said. "Parsis are emigrating to the US, the UK, Australia and the Middle East. If you look at the numbers, the 1982 census said there were 71,630 Parsis and the latest census showed 69,601. So you have 2,000 fewer Parsis in India, but I think that more than 2,000 have emigrated in those 20 years." Mr Mistree said it was possible the community's numbers in India were declining a little but he insisted the solution was not conversion. He said his faith had never permitted conversion and there was no evidence of Zoroastrians proselytising or seeking to convert people of other faiths. Asked why the ethnic purity of the Parsi community was such an important issue, he said: "It is the ethnicity that has kept this religion alive for more than 3,500 years."
He has said he has not yet decided whether he will stand for election to the new council though he claimed there was pressure on him to do so. The Wadias said they will not stand because they are less interested in the politics than they are in promoting their version of the faith. But they have suggested to their supporters who they might vote for.
So the Parsi community of Mumbai is preparing itself for what is certain to be a long and heated contest. Minoo Shroff is the outgoing chairman of the panchayat and is standing down after 21 years. In that time, he said, the board had done what it could to help boost the community, including making payments to families with a third child, operating a free fertility clinic and set aside housing for newly-weds.
Yet he too admitted this had been insufficient to counter the falling numbers. He said, somewhat wistfully: "What we need is early marriage and encouraging people to have families."
Other isolated religious communities
This Protestant group in the US and Canada has about 200,000 members. They reject technology that might damage their society; they also maintain their privacy and wear plain clothing. The whole population came from a few hundred settlers to the US in the 18th century. Inter-marriage has led to a high occurrence of children born with genetic disorders.
The Shakers' commitment to celibacy has led them to the brink of extinction – there were only four living members in 2006. The group – their lifestyle is based around emulating how Jesus lived – was founded in Manchester in 1747 and moved to America in 1774. New members can only be obtained through conversion or the adoption of children. The last active Shaker community is in the US, at Sabbathday Lake in New Gloucester, Maine.
This ancient religion shares its roots with Judaism, Islam and Christianity and is based in Iraq, where only 5,000 remain, having been forced out by fighting and forced conversions by Islamic extremists. Fewer than 70,000 remain across the world.