Medusa's Gaze and Vampire's Bite: The Science of Monsters (28 page)

Maintaining a distance while spitting is equally well founded
upon reality. Many predators go to great lengths to stay away from their prey when they attack. Komodo dragons make a single venomous bite and then back away so the toxins can do the killing for them.
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Venomous snakes do the same, allowing their venom time to take hold. The reason for these behaviors is thought to be that struggling prey can cause a lot of damage as they make their last attempts at survival. If a predator knows it has delivered a fatal or debilitating attack, there is no point in risking injury when dinner will be risk-free in just a short while.

The combination of such realistic traits in the dinosaurs along with the message that natural systems are totally unpredictable reinforces an image of the natural world as inherently dangerous to interfere with. In a sense, Jurassic Park makes Mother Nature the monster and the dinosaurs her tools for attack.

While snakes, as discussed throughout this book, certainly represent fears all on their own, a critical question to ask is whether there is any substance to Malcolm’s arguments. Is the natural world really so chaotic and fierce that any attempt to intervene is going to lead to disaster?

Even though humanity has not played God on the scale that the geneticists do in
Jurassic Park,
there has been a lot of ecological meddling in the past hundred years that is not really much different. One example stands out.

Shortly after colonists arrived in Australia, sugarcane started being grown in the warm and wet northeastern corner of the country. The environment was perfect for the crop and yields would have been incredibly lucrative—if it hadn’t been for the presence of a beetle. Unfortunately for the Australian farmers, the native cane beetle was fond of sugarcane. The adults of the species readily chewed up the plants while the larvae destroyed the roots.

In the early 1930s, the Australian government started considering the possibility of using nature against nature. Ideas were floated for bringing in a predator that could dramatically reduce cane beetle numbers and the government ultimately settled upon the cane toad from Hawaii, a carnivorous amphibian with a ravenous appetite for beetles.

The toads were introduced in 1935 and dismayed everyone when they were found to prefer insects other than cane beetles. Their taste for other insects was not a particularly large problem for the Australian environment, although it frustrated sugarcane farmers whose crops were still being destroyed by beetles. What proved disastrous was the fact that many Australian predators attacked the fat and slow-moving toads.

Cane toads have poison glands in their bodies, and unless they are eaten very carefully, their poison kills animals that consume them. Moreover, they were easy targets, which made matters worse since they were so readily hunted by Australia’s unique (and often rare) predatory marsupials, birds of prey, and snakes. The predators ate the toads and died in growing numbers. Having no successful enemies, the toads have today taken over the northeastern corner of Australia and continue to expand their territory. Native predator populations in the region respond by dwindling. Australians hunt the toads aggressively and scientists are working on ways to interfere with toad fertility. A solution may arise in the decades ahead, but there is no denying that playing God and installing the toads in the first place has created an ecological nightmare and cost Australia dearly.

In the Grand Canyon, human meddling with the environment has caused similar damage. Dams have been on the Colorado River for nearly a century. However, there were no dams upstream of the Grand Canyon until 1963, when the Glen Canyon Dam was built. At the time, the idea of damming the river above the canyon didn’t alarm anyone: Dams were popular, and cheap, clean hydroelectricity seemed like a good thing.

By the 1970s, serious long-term effects of the Glen Canyon Dam were becoming apparent. Downstream from the dam, the beaches
that river rafters were used to camping on had eroded to half their original size and the National Park Service noticed that numerous native fish and animal species were vanishing.

Extensive analysis of the Glen Canyon Dam and many other dams around the world revealed that when dams slow water flow, they also disrupt the movement of sediment that the water is carrying. The principle behind this effect is relatively simple. When water moves slowly over bits of sediment on the river bottom, the force of the water might make the sediment roll along the bottom, but unless the sediment is very fine, like mud, it won’t get picked up. When water moves quickly, however, the situation changes, and even relatively large grains of sediment can be carried away by turbulent water flow. In raging floods, small rocks and even boulders can be swept away.

Geologists realized that in the reservoir behind the dam, water was dropping just about all the sediment it was carrying. Since the water had been unmoving for quite some time, when it was ultimately released past turbines, it carried little sediment and came out the other side of the dam crystal clear. This was a problem for fish downstream that depended upon sandy coves and rocky habitats to hide in, but, like the cane toad situation in Australia, it was the unintended consequences of introducing a foreign species that proved disastrous.

Humpback chub, a rare species of fish unique to the Grand Canyon, were not deemed impressive enough to interest fishermen. To compensate for this, the Colorado River was seeded with trout eggs and a population was enthusiastically nurtured to support fishing tourism.

Trout are voracious clear-water predators that eat other fish. Humpback chub, in contrast, depend upon cloudy water to hide from danger. By building the dam and introducing new predators, humans made it easy for trout to spot and eat humpback chub. Today the chub survive in just a few of the small undammed streams feeding into the Colorado River. Whether they will survive in the wild for very much longer is anyone’s guess, but they are now classified as just one step away from extinct.

To manage all of these problems associated with the Grand Canyon, the U.S. Geological Survey, in collaboration with numerous federal agencies, has taken something of a “nuclear” approach and, on several occasions, fully opened the Glen Canyon Dam floodgates immediately after heavy rains to bring sediment down cliffs and into streams to maximize the sediment’s spread through the Grand Canyon. A lot of questions are being raised about the effectiveness of this approach, but the fact that such desperate measures are being taken hints at the severity of the problems created by a reprehensible lack of foresight.

With these two tales of outstandingly bad environmental management in mind, Ian Malcolm’s argument of nature being an uncontrollable force seems accurate. Yet as severe as these two ecological catastrophes are, humanity has not always left the natural world mangled.

Yellowstone National Park in northwestern Wyoming is home to a great diversity of animals. Visiting the park is very much like taking a safari, with a drive through the Yellowstone area rarely avoiding a traffic jam created by bison, elk, moose, or bighorn sheep that have no appreciation for roads or traffic.
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Tourists often come away with the impression they have seen one of the few truly pristine wild places left in the world. Rather remarkably, they are wrong.

The story begins with pack rats, little rodents that often build their homes in rocky crevices. To construct their nests, they collect anything and everything from their habitat that piques their interest.
In the modern day, this unfortunately means they frequently pick up shards of glass, bottle caps, and other bits of junk, but long before humans made a mess of things, they collected feathers, plant material, and bone. The pack rats then brought back their findings and urinated on them. Bizarre as it sounds, their urine binds their odd collection together into something of a nest.

Paleontologists have long been interested in pack rat nests, or middens, as they are called, because pack rats are nonmigratory animals that stick with the same nest location for many generations. Each new pack rat brings in new collected material, dumps it on top of old material, and solidifies it into place by urinating all over everything. Indeed, in the past few decades, paleontologists realized that some middens could literally be thousands of years old and that they represented a vast store of preserved bones unwittingly collected by pack rats. They were like little paleontological gold mines.

In the early 1990s, as paleontologists led by Elizabeth Hadly at Stanford University were surging forward with their analysis of small bones found in Yellowstone middens, ecologists were asking serious questions about the park’s ecosystem.

Elk seemed to exist in greater numbers in Yellowstone than in many other wilderness areas in northern North America. In addition to this, coyotes, which traditionally function as scavengers in most ecosystems, were found hunting larger animals than those they would usually pursue and were behaving more aggressively than coyotes in other regions. Some researchers suggested that this behavior was due to the absence of wolves, another large predator, which until 1923 had been living in Yellowstone but were wiped out by deliberate hunting.

Controversy raged over this issue. Many argued that wolves had artificially been in the Yellowstone area only during the late 1800s and early 1900s after being pushed out of lower-elevation areas where Europeans were expanding their settlements in the Great Plains. Yet Hadly’s team disproved this theory.

Hadly found wolf bones that were thousands of years old in pack rat middens, proving that wolves had been in the Yellowstone area
long before humans ever entered the picture. Her findings led ecologists to realize that wolves really were supposed to be living in the area; human activity had not artificially shoved them into the region. A recent local wolf extinction, caused by people, was the reason for coyotes functioning as predators and for the overly large populations of elk. With this in mind, the solution seemed simple: Reintroduce wolves to the park. Ultimately, to the chagrin of many ranchers and farmers in the area, they were returned to Yellowstone in 1995. Like
Jurassic Park,
animals driven to extinction had been brought back to the land they once roamed.

In the 1970s, Crichton’s description of an uncontrollable, dangerous natural world was a reasonable conjecture. But scientists in the fields of ecology and conservation biology are getting better at making models of the systems they are thinking of tampering with. They also are studying past ecological activity by looking at fossils of the same animal over time so they can more accurately predict the effects of their proposed actions. This improvement in modeling is comforting, since global warming will require a great deal of human intervention if the world’s diversity is going to remain intact as Earth continues to warm up. Indeed, governments are hiring paleontologists to analyze fossil ecosystems that existed during earlier times of global warming in order to work out how modern ecosystems are going to alter as climate changes.

In theory, as such environmental tinkering improves, the argument made by Ian Malcolm in
Jurassic Park
should weaken. This, in combination with the fact that dinosaurs cannot be resurrected using the methods outlined in the film, should make these creatures wane as monsters in popular culture during the decades ahead.

Yet resurrection of ancient beasts is not entirely out of the question. Hadly’s team was able to find intact DNA in fossils thousands of years old in North and South American ecosystems. Hadly has no interest in even considering the resurrection of extinct beasts, but there are more than a few groups keen to make a lot of money by bringing back something like a woolly mammoth. The idea has led to interest from both the research community and the general public.
To some it just sounds exciting; to others it is a great challenge to be tackled. To pursue it, two avenues are being explored.

Some researchers are looking for germ cells, like sperm and eggs, in mammoths that were covered in ice in Siberia thousands of years ago. No research teams have succeeded in finding any such cells intact, but even if they were to do so, they would then need to use an elephant egg cell or sperm cell to partner with whichever mammoth germ cell they found to create a few “half mammoths.” These half mammoths would then need to be intensively inbred with one another until a “near mammoth” that was only 1 percent elephant was created.

The other option for creating a mammoth involves collecting standard DNA from a frozen fossil specimen and injecting it into an elephant egg cell that has had its own DNA removed. This was the process used to create Dolly, the cloned sheep. No mammoth DNA of good enough quality has been found to make such a process viable, but researchers keep finding better and better samples, so there is a chance that such a project might one day prove successful.

Yet hope for resurrecting species is misguided. Not only is our planet in the exactly wrong climatic period to sustain these ice age beasts, vast resources are going to be required to make a project like this work, resources that could be used to save the many critically endangered animals on the planet. “How can we justify ‘bringing back’ animals when we are at a loss to preserve the diversity on the planet today?” asks Hadly.

A resurrected mammoth would inevitably end up in a zoo, since no natural habitat exists for such a creature. In contrast, if the carnivorous marsupial the Tasmanian devil goes extinct in the decades ahead—which is likely given that devil populations are dying out from a poorly understood cancer that gives them horrendous facial tumors—resurrection technology could much more sensibly be used to help their populations remain in their environment and survive the epidemic. There are even reasonable arguments for potentially resurrecting very recently extinct animals like the passenger pigeon and the Tasmanian tiger, another carnivorous marsupial that died
out in the 1930s. These animals went extinct as a direct result of recent human activity, and their habitats are still more or less intact. Indeed, their habitats, similar to that of Yellowstone, have been thrown out of whack by their absence. From the perspective of maintaining ecological balance, pouring resources into resurrecting some animals makes sense to set things right again, but only after all available resources are expended to stem the tide of destruction that is wiping out ever more species. It is, after all, much easier (not to mention cheaper) to keep an extremely rare species alive than to attempt recovering one from beyond the grave.