In the depths of Sussex, less than 50 miles due south of London, a big building is beginning to emerge from a huge hole in the ground. Think of it as a big and very important cellar, with some extra floors on top. By the year 2000, it will be the  Millennium Seed Bank (MSB), biodiversity's insurance policy. The Seed Bank, an outpost of the Royal Botanic Gardens, Kew, aims to hold all 1,400 species of the United Kingdom's national flora by the time it opens for business. Over the following ten years the plan is to bring its total deposits up to 25,000 species, roughly 10 percent of the world's flowering plants.

Roger Smith was instrumental in setting up Kew's first Seed Bank, and he now heads the Millennium Seed Bank department. He is very optimistic. 

"From what we know so far, 80 percent of the seeds we collect will have storage lives of 200 years plus in the bank, under existing conditions. Even if we predict a storage life of only 15 or 20 years for some of the unknowns, we may well have found a better way of storing them before that time is up," says Smith. Mostly, this is not rocket science. Seeds are designed as survival packages. If scientists can extend their shelf life - and for the vast majority of seeds that is a simple matter of keeping them dry and cold - they can enhance the odds of real survival.

The idea is to buy time: time for human populations to stabilize, time for habitat destruction to cease, time for human life to become a bit more sustainable. If all that happens, and if the seeds remain viable, there will be a chance of restoring lost biodiversity from the Seed Bank's chilly vaults.

The MSB will consist of an underground vault in which the seeds, having been carefully prepared and dried, will be stored at -20°C. Above will be research laboratories, preparation areas, and displays to help visiting members of the public understand what is happening. One of the more startling proposals involves large viewing windows, through which visitors can peer at the scientists going about their work.

Seed Bank staff are not all enthusiastic. "I'm not sure I fancy the idea," said Steve Alton, coordinator of the U.K. collection. "But the seed cleaners sit there for hours plugged into a Walkman; it wouldn't bother them."

The Seed Bank's surroundings will reflect its work. "Display beds will recreate eight different British habitats," said Simon Linington, Seed Bank manager. Most of the seed for that will be harvested fresh, but some will deliberately come from the deep freezes, to show it can be done. The existing Seed Bank allowed Stinking Hawk's Beard (Crepis foetida) to return to its last known site, on the shingle beach in sight of a nuclear reactor at Dungeness in Kent. So what?

Linington refuses even to attempt an answer. "We're here as a resource that people can call on. Whether something should be reintroduced is not our decision." It is a decision, it goes without saying, that cannot even be contemplated unless the seeds have been banked. There will also be oaks, grown from local acorns, that exemplify one of the Seed Bank's problems: not all seed can be stored cold. Some seeds - and oaks are a perfect example - are recalcitrant, meaning they cannot be dried down, and so are damaged by low temperatures. Kew is already researching ways of extending storage for recalcitrant seeds, and with the new Seed Bank, hopes to take these studies further.

If they do bank seeds of the entire British national flora, it will be a first. No other country has even attempted as much, and with 317 species officially threatened, it is worth doing for its own sake. But it is also politically valuable. "How can we persuade governments in other countries to conserve their genetic resources if we are not seen to be doing the same at home?" Linington asks.

It is those other governments that are the MSB's raison d'être. A single processing center is much more efficient than scattered national seed banks, even if only as a backup, and Kew was an excellent starting point. 
 

Plant breeders had long stored crop seeds cold and dry to prolong their life. Smith simply adapted that idea for wild plants. "Kew saw the potential of the technique for conserving endangered wild species," he said. "Effectively, we pioneered the use of seed banks in conservation."

By 1990, there were some 8,000 samples of 3,500 species in the vaults. With ever-more plant species threatened in the wild, scientists were beginning to appreciate that seed banks had a role to play in conservation. Kew's Seed Bank, alas, was neither big enough to do the job properly, nor small enough to ignore. Smith was charged with finding development money. The Rio conference of 1992 and the  Convention on Biological Diversity (CBD) seemed at first a godsend. After all, the CBD's three central aims are the preservation of biodiversity, sustainable use, and sharing of benefits - a perfect fit with a seed bank for the world.

But despite the almost unseemly haste with which the U.K. government rushed to embrace the Convention, no new money was made available. Rio had established the Global Environment Facility, which could fund country collections, but not the core costs of storage; no national government seemed willing to shoulder that burden. Enter Britain's National Lottery. Some Lottery largesse is earmarked for projects that are "able to look back over the past millennium and forward to the next." The  Millennium Commission asked the British public how best to celebrate the year 2000 - free beer and fireworks were the overwhelming preferences. But with that out of the way, science and the environment were high on the list.

"We could meet both science and environment," Smith explained. "We could look at seeds living forward for a thousand years, some of them, and we could go backwards, not only millennia, but millions of years of evolutionary history." The estimated total cost of the project is £72,491,500, of which the Millennium Commission is contributing £29,897,500, with the rest coming from business sponsors and donations. Smith says that the source of the money has made his life much more interesting; because the MSB was competing against opera companies and sports stadiums. "I could be a bit more red in tooth and claw."

Against other scientific proposals that include, for example, studies of sustainable agriculture or improvement of plant taxonomy, Smith could never be certain the MSB's needs were paramount. But against an opera house or rugby stadium, he could be unequivocal that a Millennium Seed Bank needed the money more. This is emphatically not a philistine argument. "Opera is an enjoyable luxury, and if it is good enough my kids will get to see it. But there's no champion for the plants. If Kew and its collaborators don't do it, who would stand up and say it should be done?"

Lottery funding buys Smith an even greater pleasure. "I find a certain happy symmetry that the money is gambled by people and we have [used it for] a biological insurance policy intended to ameliorate the gamble that the whole of humanity is playing when it adopts nonsustainable development."

The bigger gamble, perhaps, is that the Seed Bank may not pay off. "Conservation is only happening when the seeds in the bank are used to grow new plants. Up till then it is just preservation," Smith points out. The Seed Bank's guiding philosophy, as Smith sees it, is essentially precautionary. "We've spent a small amount of money - what's £70 million going to get you . . . a good football team? If we arrive at our destination safely then we will have spent our money on a safety belt we didn't need. I can live with the risk of appearing foolish to history - with kids banging on my window when I'm 70 saying 'silly old bugger.' If, on the other hand, the Seed Bank's work becomes valuable, we'll say 'thank God somebody got off their bums and did something about it.'"