Authors: Bill Schutt
Dark Banquet (36 page)
*113
Basically, this refers to all of your property except pets, plants, and food.
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As it turned out, all three of these compounds were extremely toxic to humans and most other forms of life. As vividly portrayed in Rachael Carson's landmark book
Silent Spring,
pesticides like DDT caused long-term environmental and health effects. Eventually, the alarm raised by
Silent Spring
over DDT would launch the modern environmental movement, and by the mid-1970s malathion, lindane, and other compounds known as organophosphates and carbamates were banned from use as pesticides in the United States and other countries.
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*115
On a related note, “sticky traps” used to trap insects like cockroaches don't work against bed bugs, which are more likely to travel and hide
under
the trap than run across its gooey surface.
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Essentially, you start with one cell, its genetic material divides, its cytoplasm divides, and you end up with two identical daughter cells.
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According to the
Scrub Typhus Information Paper,
published in 2005 by the U.S. Army Medical Research and Material Command, there were 5,441 cases of scrub typhus, resulting in 283 deaths among U.S. Army personnel in the Asia-Pacific theater during World War II.
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*118
Using this same rationale, it's easy to see why bootleg antibiotics or antibiotics of unknown quality are a very bad thing.
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â 119
In addition to differences in diet, chiggers are smaller than adult mites and have six legs rather than eight.
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*120
Ontogeny is the development of the individual from fertilized egg to adult.
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DNA replication (i.e., DNA synthesis) is the process by which the double-stranded DNA molecule is copied before cell division (resulting in two identical double-stranded DNA molecules and thus ensuring that each of the two resulting cells contains a full copy of the original genetic blueprint).
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Alternately, as we'll see, mutations that affect the
sequence
of developmental events can also provide variation that serves as the raw material for evolutionary change.
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*123
Long before anyone else figured it out, Lamarck actually nailed down the fact that an environmental change like the one just described was necessary in order for evolution to occur.
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Much later, a group of couch-bound scientists came up with an equally tricky question: “Why aren't the children of professional bowlers born with super bowling skills?” Presumably this question arose in the mid-1960s, when pro bowling became a wildly popular televised sportâa phenomenon in itself that has troubled many evolutionary biologists.
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And just as important, only if those changes occurred in that individual's gametes (their sperm or egg cells). Somatic mutations (like cancer), which occur in nonsex cells (like those of the skin), are not passed on to the next generation, although inherited mutations in a person's DNA could predispose him or her to develop skin cancer.
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*126
According to entomologists R. Chapman and H. Shepard, “Mites infest foodstuffs to such an extent that the entire mass may appear to be in motionâ¦If some of the flour which is suspected of containing mites is piled in the light, the mites will crawl away from the light and the pile of flour will usually flatten out.” And in a quote that immediately reminded me of Lou Sorkin and his citronella-scented bed bug colony, the authors stated that “when present in large numbers they give off a sweetish, musty odor, which is so characteristic that one who has had experience can detect their presence without having seen them.”
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The word
scabies
comes from the Latin
scabere,
“to scratch.”
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*128
These include apples, pears, blueberries, almonds, pumpkins, and squash.
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*129
The malnutrition hypothesis posits that bees forced to pollinate large monoculture farms are missing something in their diets in much the same way that a dog fed nothing but bread would experience physical harm from such a diet and eventually starve to death. On a related note, weather (e.g., drought) can also negatively affect pollen-producing plants, resulting in pollen that is deficient in the nutrients the bees require.
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Researchers have identified both of these viruses in nearly all hives with CCD but not in control hives.
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In a development eerily similar to CCD, White Nose Syndrome has been killing thousands of hibernating bats in upstate New York and Vermont. The most obvious symptom is a white fungus around the nose of stricken and dead bats. Experts suspect that the fungus may be a secondary problem and that something else is killing the animals. In a press release from the New York Department of Environmental Conservation, bat specialist Alan Hicks said, “What we've seen so far is unprecedented. Most bat researchers would agree that this is the gravest threat to bats they have ever seen. We have bat researchers, laboratories, and caving groups across the country working to understand the cause of the problem and ways to contain it. Until we know more, we are asking people to stay away from known bat caves.” The DEC statement went on to say that, “Bat populations are particularly vulnerable during hibernation, as they congregate in large numbers in cavesâin clusters of 300 per square foot in some locationsâmaking them susceptible to disturbance or disease.” Adding to the problem, most of the bats known to hibernate in New York do so in just five caves and mines. “We have lost more than 90 percent of the animals at the two sites for which we have good survey data,” Hicks told me. “The problem is also expanding into new sites and now involves hibernacula harboring over 200,000 animals.” Bat biologist John Hermanson was also deeply concerned about what was taking place. “We've got caves with eight bats in them. There used to be thousands.”
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Fleas are blood-feeding insects belonging to the order Siphonaptera (which numbers around 2,100 species). Like the chiggers that normally prey on rodents, but transmitted pathogenic bacteria to troops in Asia and the Pacific, fleas preying on rats transmitted the Black Plague to fourteenth-century Europeans. Following trade routes and the humans that plied them, black rats
(Rattus rattus)
spread across the world. As rat populations exploded, the fleas they carried began to encounter (and bite) humans on a regular basis. The plague struck with wavelike regularity throughout the Dark Ages, spreading inland from major ports, where it devastated cities and erased the inhabitants of entire towns. With no cure, the Black Death wiped out a significant portion of the human race (with estimates running as high as seventy-five million people killed). What saved civilization, apparently, according to one hypothesis, was that black rats were eventually replaced by another species, the brown rat
(Rattus norvegicus),
whose fleas were less likely to bite humans.
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*133
Tick and chigger researchers actually collect their specimens by attaching a piece of rough fabric (like fleece or flannel) to a rodlike handle. These “flags,”“drags,” or “drag cloths” are then passed across the tops of tall grass or other low-lying vegetation in the hope that questing parasites will latch on.
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*134
Unlike insect respiratory systems, ticks have only two spiracular openings. Additionally, many ticks have a gill-like structure called a plastron that extracts oxygen from water, thus explaining why ticks can survive long periods of submergence. Although the mechanism is still being investigated, it appears that oxygen diffuses into the plastron and then into the tubelike tracheal system where it travels to supply the tick's body.
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*135
Around 15 percent of patients who contract Lyme disease also report long-term neurological problems ranging from memory loss and diminished cognitive function to Bell's palsy (which is characterized by temporary facial paralysis), and even meningitisâa sometimes life-threatening infection of the protective tissues (the meninges) covering the outer surface of the spinal cord and brain. Meningitis can produce stiff necks, sensitivity to light, excruciating headaches, and far worse. The question of whether these long-term effects are actually caused by Lyme disease is a matter of current and heated debate.
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Synovial fluid is found within the articular capsules that enclose joints like the knee, hip, and elbow. Bathing the cartilaginous surfaces where the bones meet, this slippery substance has the consistency of egg whites. It functions as a lubricant and also provides nutrients to the surrounding tissues of the joint. Apparently, some researchers (like Dr. Yeh) believe that synovial fluid also provides a safe haven for the corkscrew-shaped
Borrelia burgdorferi,
allowing it to elude the body's immune system (as well as administered antibiotics) and produce the chronic symptoms sometimes associated with Lyme disease.
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Most notable was a multicenter study led by Dr. Mark Klempner of Boston University School of Medicine.
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Lymerix, the “breakthrough” vaccine for Lyme disease, was produced by the drug company GlaxoSmithKline and available between 1998 and 2002, when it was suddenly withdrawn from the market.
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On a related note, a recent lawsuit claims that the makers of Lymerix neglected to alert physicians and the public that around 30 percent of the population has a predisposition to an incurable form of autoimmune arthritis that can be triggered by the high concentrations of a specific bacterial surface protein contained in the vaccine.
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My students were convinced that Kilometer 41 had been named for how far it was to the nearest flush toilet.
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The
Victoria Amazonica
crewmember who lost a chunk of his thumb to a black piranha on our first trip to Brazil may have a slightly different opinion on the matter.
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During a recent interview, candiru expert Dr. Stephen Spotte voiced extreme skepticism that this garb had anything to do with preventing candiru attacks and plenty to do with avoiding pests like ticks and sharp objects such as thorns.
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Dr. Spotte is a marine scientist and a prolific author He has published on topics ranging from modern zoos to mermaids. “I'm just an ologist,” he told me.
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*144
This would be comparable to aliens capturing a jockey and a basketball player, then calling them different species because of the observed size differences. Presumably, if they had a greater sample size (a whole town, perhaps), they'd realize that they were looking at a single species.
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In some ways this gas exchange mechanism is similar to the one that exists between the respiratory airways of terrestrial vertebrates and the tiny alveoli located in their lungs. Oxygen (which is at a higher concentration in the water surrounding the gills than it is inside the feathery gill filaments) diffuses from the water into these ultra-thin-walled structures. The oxygen then passes into blood being carried by tiny vessels within the filaments (in much the same way as oxygen passes from alveoli into the capillaries that surround them). These blood vessels then carry the oxygenated blood away from the gills to be distributed to the tissues of the fish's body. One major difference between the circulatory systems of fish and other vertebrates like amphibians, reptiles, birds, and mammals is that in fish, the oxygenated blood does
not
return to the heart before being pumped to the body. The fish heart is a rather simple, two-chambered pump (one atrium and one ventricle), rather than a three-chambered (amphibians and most reptiles) or four-chambered structure (crocodilians, birds, and mammals).
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A recent claim by researchers Jansen Zuanon and Ivan Sazima that candirus feed passively (i.e., the blood pressure of the prey literally pumps the blood into the candiru's digestive system) remains untested and Stephen Spotte is extremely skeptical. “From watching candirus feed, it appears that a rapid pumping mechanism of some sort is being used. Were ingestion passive, no such pumping activity, in fact, no movement would be necessary. The process would be like filling a bottle of water from a faucet.”
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*147
The identity of the patient (Silvio Barbossa) was revealed in a more recent
Animal Planet
segment on parasites.
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In separate trials, they added solutions of urine, blood, and ammonia to tanks containing captive candiru, and in each case they saw no visible change in the candiru's behavior. In fact, only when they released a fish into the water did the candiru perk up.
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*149
Interestingly, humans with hookworm infections are half as likely to have asthma or hay fever. The idea is that some parasites survive by down-regulating their host's immune system. With its primary defense mechanism throttled back, it's far less likely that the body will mount an inflammatory response against a harmless allergen or attack its own tissues. On a related note, it appears that in addition to selecting for more antibiotic resistant bacteria, our 99 percent germ-free culture has resulted in hypersensitive immune systems. The end result is an increase in the incidence of asthma, allergies, and some autoimmune diseases.
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