However engaging and open-ended an intellectual problem this pull toward rarity is, it has some disquieting implications for the environment. One of these implications comes from the fact that we are not all that quick to spot rarity. We’re very good at detecting a pattern that differs from a bunch of others, or at concluding that the mustache wrapped around that guy’s ankles is the longest we’ve ever seen, but we aren’t as good at recognizing processes. By the time we pick up on something—hey, have you noticed there aren’t a whole lot of passenger pigeons around anymore?—it might be too late. For decades the live oak population has been in decline on parts of Stanford University’s land, but few people realized it because the trees live for centuries, and only biologists noticed the absence of saplings. How many warm winters and dry summers had to pass before someone noticed global warming? Our nervous systems have evolved to detect sudden changes, but rarity, especially in other species, is all too often achieved by a gradual fading away.

Another problem arises because we’re more emotionally responsive to some signs of rarity than we are to others. While many nature lovers are drawn toward "last best places," as endangered ecosystems are sometimes called, we are generally more responsive to animals than to natural systems, and more responsive to certain species—the ones that are cute, smart, or particularly exciting and dangerous. Thus, the World Wildlife Fund uses a giant panda bear as its symbol rather than the vanishing bamboo forests that sustain the pandas. But you can’t save pandas without saving the ecosystem they depend on, and the pull of the rare panda (or mountain gorilla or California condor) sometimes produces interventions that don’t see the forests for the tree frogs. The millions spent on California condor preservation in captivity will be wasted unless an environment can be created that simulates their original habitat—lots of big carcasses free of pesticides and poisonous lead bullets; few people with firearms anxious to shoot at anything that moves. Przewalski’s horse is a similar case. It’s been kept alive in zoos, and it is now being reintroduced into central Asia. If conservationists relax their guard, the species could suffer the fate of its wild ancestors, perishing under competitive pressure from domestic grazers and being devoured by starving Russians.

Now suppose that, out of some combination of stupidity, shortsightedness, corruption, and venality, the country allows half of that rare place to be squandered for immediate profit. Too many tourist lodges are built within it, generating too much waste that is dumped into the rivers. A cousin of the autocratic president discovers how profitable it is to crank up that logging or mining operation on the edge of the preserve. A moronic secretary of the interior decides to privatize national parks. A little hunting is allowed for big permit fees, rangers are bribed by locals to let their cows graze on parklands. Someone pockets a bundle and this home of the rare is diminished substantially.

What happens next? News of this outrage winds up in conservation-oriented media. Perhaps they report on the process that has made the endangered more endangered, or perhaps they just concentrate on the depressing end product. In either case, the bottom line is the same: “The Last of Borneo’s Orangutans?” “The Diminishing Elephant Herds of Africa,” and so on. All of it translates into the same message. If you’re planning to see this, do it soon at any cost, because it’s going fast. Thus we have a lethal paradox—if you control something large that is famously, magnetically rare and you toss away half of it for a quick profit, the remaining half becomes twice as valuable. After a certain number of halvings, of course, you reach a point of diminishing returns, of no return, the exponential slide into oblivion. But in the meantime, the squandering gets rewarded because we like our rarity.

Don’t confuse this depressing example of supply and demand with the economics of malevolent exploitation—as poaching diminishes the numbers of rhinos, for example, the value of the putatively aphrodisiac horn increases, thus increasing the incentive for further poaching and raising the value even further. This is a much subtler variant on the economics of scarcity, one with three components—the immediate financial rewards of misusing fragile ecosystems, the fact that the consequences of such misuse can be reported far and wide, and the desire of many Westerners to see, to commune with, the planet’s remaining wild places and its inhabitants, whatever the cost.

This paradox not only applies to the circumstance in which some ecological treasure gains value as it becomes rarer but to the inverse case as well, in that something endangered will lose value as it creeps back from the edge of extinction. The Australian corporation Earth Sanctuaries establishes reserves and breeds rare animals to stock them. The commercial value of the company is based in part on the value of the animals, which is in turn tied to their scarcity. Each nearly extinct wallaby or bandicoot has great value, but the more successful the company is in building up their populations, the more the value of each individual dwindles. There’s a conflict between biological and economic success that would make it mighty hard for an Earth Sanctuaries to be delighted about “curing” the problem of endangerment and thus put itself out of business.

There may be some solutions lurking here, but they are neither obvious nor easy. We certainly don’t need to cure ourselves of our attraction to rarity. Nor should someone who has saved over a lifetime for a trip to the Serengeti feel morally obliged to forgo it. If tourists do not support the ecotourism effort that allows people to view the Serengeti’s Pleistocene herds, then they’ll soon end up in cook pots and be replaced with cows and goats. As usual, the most effective solutions lie with those least likely to implement them: the nations and organizations benefiting from the perverse economic incentives.

It is easy to see how our primal attraction toward the rare can cause us to doom something precious when we act with the worst of intentions—were there someday only one wild elephant left on Earth, there would be no shortage of scum willing to bid the heavens for the chance to stalk and shoot it. But it is surprising to think that we may inadvertently help to doom something precious, and damage our civilization in the process, while having the best of intentions.