The Ragged Edge of the World (29 page)

What this means is that the factors that keep small animals small and big animals big may no longer apply. Another scientist I spoke with, Mark Lomolino, who with James H. Brown coauthored the classic work
Biogeography,
noted that among island mammals, large animals tend to get smaller, while small animals tend to get larger, with the tipping point being creatures about the size of a red squirrel. He suspected that given the absence of predators and the uncertain food supply of islands, the smaller offspring of large mammals such as mammoths survived better, eventually driving the mammoth on the island of Crete down to the size of a Great Dane. The absence of predators and competitors, meanwhile, enabled small animals to grow larger to take advantage of new food sources.

Thus Anguilla once was home to a 300-pound rodent dubbed
Amblyrhiza
. Consider this rodent together with the Cretan mammoth and, presto, you can see the magic of the island rule: rodents larger than elephants.

While there may be powerful advantages to being the biggest or smallest—an exceptionally large animal may have the edge in competing for a wider variety of resources or in surviving during lean times, while a small one may best elude predators—either extreme involves fateful tradeoffs. The bee hummingbird may have few enemies, but with a heartbeat roughly twenty times that of a human, it has a nonstop need for energy; a person with an equivalent metabolism would have to consume 100 pounds of food a day. Such specialization makes these species extremely vulnerable to ecosystem disruption. In Humboldt, Tony pointed out a plant called
Dracaena cubensis
, which is so closely linked to the rocky, magnesium-rich and nutrient-poor local soil called serpentine that botanists haven't been able to grow it in Havana.

The absence of predators affects animals in other ways besides size. In Humboldt Park, for instance, Tony said there is a snake called
Alsophis
. On the mainland the snake's near relatives are poisonous, but while the variant on Cuba has sacs to produce venom, it has lost the ability to inject the poison. Testimony to the absence of predators is the fact that there are no poisonous snakes on Cuba.

Another life-form seizing the brass ring of ecological opportunity has been the lowly snail. Colorful tree snails of the genus
Polymita
snails have proliferated wildly in Cuba, particularly in the hills of Pinar del Rio, where they use the limestone to build their shells. Humboldt has
Polymita
snails as well, including one species that occurs in three colors, yellow, red and green. The pretty shells are in such demand (we passed vendors selling them beside the road) that the snails have become endangered, and in turn, the snail hawk (more formally, the hook-billed kite), which feeds exclusively on this one species of snail, has also become critically endangered.

Which brings us to the larger point of this exercise. There are no large mammal predators on Cuba, except for one that arrived a mere 7,000 years ago:
Homo sapiens
. Humanity's relatively recent appearance on the island may explain why some animals persisted longer there than on the continents. The giant sloth, for instance, vanished from the South American mainland roughly 11,000 years ago, presumably hunted to extinction, but survived for another 5,000 years in Cuba. Humans probably did in the giant owl that once ran around the island as well. Before our arrival it had no need to fly, and whether or not the giant owl realized the fatal error of this evolutionary choice, it could not rediscover the ability to do so.

As an aside, when I first heard about the discovery of the bones of tiny
Homo erectus
–like hominids on the island of Flores in 2004, I immediately thought of this aspect of islands. Dubbed
Homo floresiensis
and nicknamed “hobbits,” these little people stood about three feet tall, had heads the size of a grapefruit, made stone tools, and cohabited on Flores with the typical assortment of island giants and dwarves—including a pony-sized elephant, a rat the size of a dog and giant Komodo dragons—until about 12,000 years ago. The remains of several hominids of all ages were found in a limestone cave called Liang Bua.

If the hobbits did represent the last living examples of
Homo erectus,
they lived past the species' extinction date by some 90,000 years, which would be astounding in itself. Some critics of this hypothesis claim that the hobbits were merely a dwarf family of modern humans, the result of random mutation that spread because of the isolation of this family. But is it possible that the hobbits were a result of the same processes that produced Flores's dwarf elephants and giant rats? If so, from what original form could the hobbits have derived—
Homo erectus
or
Homo sapiens
? I doubt these questions will be settled anytime soon, but recent analysis of the bones supports the mind-boggling possibility that the hobbits were indeed a relic of the deep past. For instance, an analysis of the hobbits' long, flat feet suggests they had more in common with early bipedal hominids, who had yet to develop a foot that facilitated long-distance running. Regardless, the hobbits stand as the most intriguing discovery of this century thus far.

The peculiar patterns of islands may seem like curiosities, but they have great relevance today, argues Mark Lomolino. For one thing, the destruction of mainland habitats due to agriculture and urbanization is turning many continents into a series of islands, and Lomolino wonders whether, for instance, the disappearance of large predators in nature reserves is having the effect of replicating the process of dwarfism on the mainland. Wilson agrees and notes that our understanding of island evolution can help us understand how to preserve natural systems everywhere. More specifically, because island species tend to be so exquisitely adapted to particular circumstances, and because they evolve in isolation from predators and parasites on the mainland, they are particularly vulnerable to disruption. That's why, says Wilson, most of the major extinctions caused by humans have occurred on islands.

Following our stop in Humboldt we made our way east and then south, first to the exuberantly tropical city of Baracoa, and then past Guantánamo to Santiago and Granma. It's a stunning drive, through rainforests and past waterfalls and the deep limestone gorge of the Yumuri River, with cliffs towering hundreds of meters high. Along the way we saw someone at the side of the road offering a Cuban parrot for sale. Tony didn't want to stop, because the parrot is endangered, and if we did stop he would have felt obligated to denounce the man and have him arrested, and he didn't want to spend the rest of our day dealing with the bureaucracy. From the look of the parrot, the species should be the official mascot of the revolution, as its olive-green feathers make it look as if it were copying Fidel's combat fatigues to demonstrate solidarity with the revolution.

Once we passed through the divide on the Nipe-Sagua-Baracoa Mountains, we descended toward the south coast, and the climate dried out noticeably in a matter of miles. On the coast we encountered thousands of melon cacti. As we drove past the DMZ that divides the American-controlled portion of Guantánamo from Cuba, Alberto helpfully provided the Cuban perspective on past American meddling in Cuban affairs. Tony wryly remarked that the 1-kilometer-wide zone, with its fences and land mines, was “the most protected place in Cuba.” He also described the Cuban city of Guantánamo as the “ugliest” in Cuba. The tamarind-lined boulevard leading up to the city, however, was quite lovely. Farther on, another boulevard was lined with
Guaiacum
trees, whose precious wood contains oils that protect it in seawater and make it an ideal material for boat rudders. In town we looked for a
paladar
(a private Cuban home that offers meals) for lunch, but settled for pizza. I noticed a number of cafés billed as vegetarian restaurants, another example of the Cuban tendency to make a virtue of necessity, as there was little meat, nor much of anything else, in Guantánamo.

The southeastern coast of Cuba has to be one of the most beautiful in the Caribbean. There are formations called marine terraces in Punta Caleta, easily visible from Parque Nacional Desembarco del Granma (which commemorates Castro's landing). Some 500 meters high, with twenty-four stair steps, each dozens of yards high, these terraces provide a dramatic record of past sea-level rises and falls. Lifted from the sea courtesy of plate tectonics, they offer paleontologists a perfect site to study past climate change. In a 1999 UNESCO report, Jim Barbarak called the terraces the most impressive coastal cliffs on the east coast of the Americas from the Canadian Maritimes to Tierra del Fuego.

The beaches are pristine, the waters clear, and the occasional lagoons rich. We stopped at Daiquiri Beach, supposed home to the drink that was made famous by the Floridita in Havana. We passed through spotless and delightful-looking towns such as Imías.

The only reminders that there was more to this tropical paradise than met the eye were the occasional billboards exhorting revolutionary fervor (the island's inhabitants don't look particularly fervent), and Alberto's continuing monologue on the revolutionary history of the island. It turned out that Alberto had traveled extensively for the regime, and, amusingly, we discovered that we might have been in Vietnam at the same time, though I was in the south reporting and he was in Hanoi doing God knows what.

It was eerie but pleasant to listen to the two running commentaries. While Alberto recounted in detail every significant event of the revolution—“Here in Granjita Siboney, Castro holed up in a safe house on the twenty-fifth of July, 1953, and then attacked the barracks on the twenty-sixth, upon which Battista strafed the house”—Tony filled in the biological significance, noting that the caves at Siboney Justisi contained a Cuban boa that sat at their mouth and caught bats as they flew in and out. (Both Siboneys are named for the aboriginal hunting and gathering tribe that settled Cuba roughly 4,000 years ago.)

We stopped for the night in Santiago in another charming colonial wreck, the Casa Granda. The hotel sits right off Cespedes Square, named, as Alberto informed me, for the “father of the country, who in 1868 set free the slaves and initiated a war with Spain.” Santiago is known for its music, and indeed, the city fairly vibrates in the evening. I stopped by a couple of clubs and was immediately mobbed by beautiful young
giniteras
(girls, often with college degrees, who moonlight as call girls). Surprisingly Alberto defended the practice, noting that each
ginitera
could support four people, but, as I was married with children, I decided that I was not going to make this particular contribution to the Cuban economy.

Our visit to Granma Park the next day prompted another history lesson from Alberto and some reminiscences from Tony. He had fond memories of climbing Mount Turquino, which is connected to the coastal park by a corridor, as a rite of passage when he was a high school student. The mountainous terrain is covered by a beautiful evergreen forest, which has the feel of a dry tropical forest on the lower slopes and gives way to a cloud forest in the upper elevations. Granma extends 17,500 hectares, and Tony hopes that it will be joined with the 30,000 hectares of neighboring Parque Nacional La Bayamesa to form a 50,000-hectare park.

On the way back into town, we stopped at a stunning vista point. I remarked that if I were the hotel-building type, this is where I'd site my resort. Tony amiably replied, “In that case, I'd be fighting you.” He went on to note that he had already won a big battle by halting a plan to dynamite the cliffs and straighten the road.

On the way back we stopped for lunch as Los Galleanos, an immaculate small resort hotel perched on a cliff and connected to the beach by a 200-step stairway. There were few tourists, and Tony remarked that what building had taken place in the area was more preparatory to an expected tourist influx than a response to current demand. That demand will come, and I only hope that Cuban officials open the valve in a cautious way that preserves the wonderful purity of this part of the island. Christopher Columbus is said to have observed when he landed in 1492, “This is the most beautiful land that human eyes have ever seen.” It still is.

After traveling back to Havana, I met, at the recommendation of Mary Pearl of Wildlife Trust, with Orlando Torres, a distinguished zoologist from the University of Havana. Short, balding and exuberant, Orlando was impossible not to like. Back then he made about $23 a month, but he was a living embodiment of the truth that if you love your work, everything else will fall into place. He offered to take me up to Zapata Swamp National Park.

If Alberto's obsession was cars, Orlando's was birds. As we entered the Ciénega Zapata, he became visibly excited. Ciénega Zapata is not only the largest municipality in Cuba, it's also the least populated, with only 9,000 permanent inhabitants. Our first destination was the Hatiguanico River, which runs westward, start to finish, through Zapata. We met up with Cesar Fernandez, the local park ranger, and hopped into a small outboard to explore the park. Cesar's park office was solar-powered (again the scarcity of fossil fuels being the driving force), and was connected to the river by a canal. Orlando proudly claimed that the Hatiguanico is one of the few rivers in the world that has no human influence for its entire length.

I could believe him, seeing how cool, delicious and absolutely clear its water was. This was as close to a wetland Eden as any place I've been since the Ndoki. At 50 by 60 miles, Zapata Swamp is the size of Delaware and is the largest wetland in the Caribbean. Orlando said that Zapata is a bit like the Everglades in structure, meaning that it is really a broad, shallow sheet of slowly flowing water. Here again, the economic crisis had protected the outer part of the swamp, as Cuba now used 50 percent fewer chemicals in agriculture, further reducing the already small burden coming from the rice fields outside the park.