As lovers of natural history, we sometimes tend to romanticize nature when we explicate its marvelous and mysterious beings, but there is a darker side to nature and it is important never to forget that. Certainly we have all seen frightening and grisly footage on TV nature programs about shark attacks and without question the closeups of the gaping maw of a Great White is enough to make even the most intrepid and avid adventurer have second thoughts. However, as shark researchers will assure you, shark attacks are relatively rare. However, my attitude toward statistics is neatly capsulized in the following anecdote. An airline stewardess was becoming increasingly annoyed with a passenger's incessant questions about the flight, the plane and, the personnel. Finally, he asked one question too many:

"How often to these kinds of aircraft crash?"
"Only once," replied the stewardess.

If you are the object of a shark attack the statistics are of little comfort. Nonetheless, it is true that there are other marine creatures that produce more fatalities, excruciatingly painful injuries, and severe wounds than sharks and it is not only sharks that provide the stuff nightmares are made of.

One group of organisms which contains a number of species which are amazing, dangerous and/or lethal to humans is the jellyfish. This is a group that contains a marvelous range of bizarre, beautiful, and deadly creatures and there is even one tiny (about 1/2" to 3/4" in diameter) freshwater jellyfish called Craspedacusta sowerbyi. An interesting psychological fact about humans in relation to creatures they find threatening is that very often the size of such creatures gets exaggerated enormously—whales that can devour entire ships, giant squid and octopi that can seize an ocean liner and pull it to the bottom of the ocean and giant sea serpents whose necks could tower over the masts of the great sailing ships. This predilection for hyperbole extends to jellyfish as well. There are reports of great flat jellyfish 25 to 30 feet in diameter in remote parts of the Arctic. It is true that the very cold water in both polar regions, because it contains more oxygen than warmer water, produces an especially rich planktonic soup and some organisms, as a consequence of the availability of such a rich food source, do grow to sizes not ordinarily found in similar groups living in more temperate environments. The largest authenticated coelenterate that I have read records of is Cyanea, or the lion's-mane jellyfish, with a diameter of about seven feet and it does indeed tend to be found primarily in Arctic oceans. But, think of it—seven feet! That's taller than you are, unless you're a basketball player. The reason for the appellation "lion's-mane" is the thick mass of golden-yellow tentacles which Cyanea possesses, about 1,200 of them which are capable of extending over 100 feet into the sea! The tentacles of coelenterates are covered with "stinging cells" or nematocysts of which there are approximately 15 types. Some nematocysts contain a toxin and the strength of that toxin can vary enormously and this variation is not merely from genus to genus. Aequorea, is generally regarded as essentially harmless and its stings will ordinarily produce, at worst, a mild rash. However, there are reports that in certain locations, with environmental seasonal changes, Aequorea can deliver severe stings of a very painful nature.

The range of reaction to the coelenterates ranges from an irritation so mild as to be barely noticeable to a fiery, intense burning (hence the name "fire coral") to masses of severe wounds along the entire areas of the body that come in contact with tentacles (as with Physalia), and these stings can produce dizziness, disorientation, difficulty in breathing and necrosis of tissue. But—enter the sea wasps, Chironex flexeri and some related cuboid medusae—these have been described as the most deadly organisms on the planet, and while this may be mildly hyperbolic, their venom can kill an adult human in 30 seconds! Some people have survived encounters with sea wasps, but are not anxious to have a second encounter. The toxins of this group and some of the other highly dangerous coelenterates induce anaphylactic shock and survival depends upon very rapid and intensive medical treatment. There is no malice involved when a jellyfish stings you; it has no brain and only the most primitive sort of nervous system, however, if you get stung, that information is of little consolation. If you are swimming or wading, avoid jellyfish, If you find them on the beach, exercise considerable caution. In the water, they are tempting because so many of them are elegant, beautiful, or fascinatingly strange. On the beach, they are intriguing because they look like glistening lumps of quivering, iridescent glass filled with water, which if touched would burst and flow away into the sand. Many years ago in my early teens, I learned otherwise. Our family was visiting relatives on the coast of California (certainly a parallel universe) and my parents and aunts and uncles were all excited because of the approaching spawning of the grunion. At the time, I had no interest in that kind of fish and didn't even know what a grunion was. I imagined that it was one of Lewis Carroll's portmanteau words which meant "green onions". However, when I learned that the beaches were closed to the grunion grabbers due to an influx of sizeable jellyfish, I got excited. Now these were "fish" I could relate to. The next day, I wheedled and whined and sighed heavily until all of the adults were willing, nay glad, to drop me off at the beach so that they might have a bit of peace and quiet.

For my age, I was a tall, thin, but fairly sturdy fellow and I was armed with a bucket, some jars, a trowel and a hunting knife—certainly a match for any beached jellyfish. As I was thrown out of the back door of the speeding car onto the beach—no, that's just my imagination taking over from watching too many old gangster films. Actually, my parents deposited me on the beach with last minute words about timetables stating when they would pick me up and giving me stern admonitions not to talk to strangers or touch dead things on the beach and especially to avoid the jellyfish. Well, of course, I didn't hear a word they said and the minute they left, I headed for the jellyfish-strewn beach. I was in for a surprise. I had expected some delicate organisms about the size of a silver dollar, but what I met with was a beach scattered with large flat jellyfish 1 to 2 feet in diameter. It was an awesome sight and I felt that I had been given a unique opportunity to witness something special.

I was cautious in my approach to these rather intimidating blobs. I approached a nice large specimen and squatted down to observe the shimmery, iridescent rainbow of colors constantly shifting in this bizarre organism as it refracted the light. I took out the hunting knife, a not very sharp hunting knife given to me by protective parents, and I gently prodded this stranded, alien creature with the point of the knife. My expectation was that it would rupture like a water balloon and that some eldritch, viscous fluid would spill out onto the sand. However, no such thing happened. It quivered a bit, just from the vibration of nudge, but otherwise, nothing. Well, I thought, it must be like a very firm aspic and I gave it a much harder poke. Quiver. Nothing else. The third time I jabbed it as hard as I could with the knife. Nothing. I wasn't about to try to pick up a jellyfish with a one and a half foot diameter and try to get it into a bucket, but I was willing to settle for a small section of it which I could study at leisure. I pulled out the trowel and began to hack at the jellyfish as though it were some mortal enemy which I was determined to dispatch. Nothing! This creature was like a great mass of virtually indestructible gristle. Had I been older and more self-conscious, I'm sure I would have thought that anyone observing me would have regarded me as demented. My efforts were to no avail; this delicate-looking creature remained impervious to my assaults. In disgust and resignation, I tossed my trowel into the bucket and headed off toward some rocky areas with tide pools. Here was an entire miniature world spread out before me. Sea anemones, starfish, sea urchins, small crabs, hydroids, barnacles, nudibranchs, and polychaete worms—I wanted to lift the whole thing up and transport it to our backyard 1,700 miles away, since I couldn't convince my parents to move to the sea coast. I had been watching and watching and the time had slipped away and suddenly I realized that my parents would be arriving in a few minutes to pick me up. At the moment, I was utterly fascinated by starfish and so, using the trowel, I carefully pried several nice specimens off the rocks to put in my bucket and in the process got pinched by a crab whose territory I had invaded.

My parents, although not thrilled by my acquisitions, did let me put that precious cargo in the trunk of the car.

When we got back to my aunt and uncle's house, I set the bucket at the back of the driveway until the next day. What does all this have to do with sea wasps? Nothing. However, it does have to do with the nightmare of the stench of rotting starfish. NEVER collect stuff you don't have the means to preserve properly!!! I tried to salvage them by taking them out to dry in the sun, but even after a week, the odor was still so ripe that my parents wouldn't share the car with my once lovely starfish.

Back to the jellyfish for a minute. One type sometimes found in abundance on Florida beaches is Physalia, also known as the Portuguese Man-of-War, a fascinating and potentially quite dangerous creature. It is actually a complex colonial organism. The opalescent blue float is filled with gas very similar in composition to ordinary air and this float can reach a length of about one foot and it has tentacles that can extend to more than 50 feet. This makes it a particular danger to swimmers who can come in contact with a mass of tentacles. The toxin in Physalia is very powerful and can produce severe lesions leaving permanent scars, but worse the pain can be so severe that it may induce shock, respiratory paralysis and thus drowning. Beachcombers need to exercise great caution around Physalia, since even dried tentacles can still discharge and produce severe wounds.

Many people in the Western world are terrified of snakes and perhaps this is a consequence of the Judeo-Christian heritage of the myth of the serpent in the Garden of Eden. Other cultures from ancient Egypt to modern India have worshipped the snake, and in particular the cobra, regarding it as sacred. I would say that I am fascinated by, but not fond of, snakes. At one time I had three garter snakes, and I don't mind grass snakes or bull snakes or king snakes or small water snakes and I really quite like blue racers, as long as they don't surprise me. However, venomous snakes and large constricting snakes are quite a different matter; I prefer to let other people deal with those. Consider this concatenation: a large snake, highly venomous, underwater in the ocean where you are swimming. That's right, sea snakes! There are related to cobras and are one of the most venomous of all reptiles; they are well-adapted to underwater life and can move very quickly; they swim in an elegantly undulating, but nonetheless, distinctly sinister fashion. These are not creatures to be dealt with casually and if encountered should be avoided as quickly as possible as they are quite unpredictable.

There are sea urchins with long hollow spines containing nasty toxins and these pincushions of the sea are deserving of respect, but with sea urchins one doesn't have to worry about being suddenly hunted down and attacked, but one does need to watch where one steps.

An intriguing spinoff of human beings' curiosity about toxic substances in some of these organisms has been the development of marine pharmacology. Interestingly, by modifying the structure of some of these toxins, altered molecules with significant potential benefits for human beings have been produced. For example, such alterations of powerful, destructive toxins have shown promise as painkillers many times more potent that what we have available now. Medicine proceeds in strange cycles. In the 16th Century, Paracelsus, whose wonderfully excessive full name was Phillipus Aureolus Theophrastus Bombastus von Hohenheim—try getting that in the space provided on government forms—, anyway, Paracelsus revolutionized "modern medicine" by rejecting the exclusive use of herbal curatives which had been the model for centuries. He had studied with alchemists, among others, and was convinced that chemical curatives had greater powers than herbal ones. He was one of those half-genius, half-madman types, and so naturally, all of his sound, inventive, medical intuitions were mixed with mysticism, astrology, alchemical nonsense, and blind prejudice—he believed that no one with red hair should be allowed to practice medicine.

His use of heavy metal compounds, such as, arsenic, and mercury, though highly risky, provided him with some spectacular successes and gradually changed one part of the development of medicine. But consider, today most pain killers are still derived from plants or compounds synthesized from plants. Thus the discipline of marine pharmacology presents an exciting set of possibilities for discovering new benefits for humans derived from animal substances. Unfortunately this promising area of research is sadly underfunded. There is a compound called holothurin, extracted from a sea cucumber, which shows anti-neoplastic (anti-cancer) activity. There are still so many secrets that we have to learn from nature and yet we are polluting, exploiting, and destroying vast parts of it before we even have a chance to begin to unravel its mysteries. Even organisms which from our perspective seem dangerous or ugly may have much to teach us. The sea wasp which can be deadly may eventually provide powerful painkillers; the sea cucumber, which few admire for its beauty, may help us combat cancer.

Earlier in this essay, I mentioned sharks. Let me tell you a brief story which helps illustrate our need to have a deeper understanding of the wonderful mechanisms which nature has devised. About a decade ago, I read an account of a scientist doing research at the Red Sea on a small flatfish know as Moses' sole (According to legend, it got caught in the middle when Moses parted the sea and so the fish got sliced in half with both eyes on the upper side and was pancake flat on the under side.) There were also some scientists at this facility who were working on sharks and had several in a large holding tank. The researcher of the Moses' sole (perhaps some of you with younger brains and better memories remember her name; I can no longer recall it) acted on a whim and asked her colleagues if she might release a Moses' sole in their shark tank. They were all astonished by what happened. A shark approached the flatfish, mouth wide open and as it seemed about to devour the Moses' sole, it suddenly backed away and, for a brief time, behaved as though it had lockjaw in reverse; it appeared temporarily unable to close its jaws. The woman scientist was fascinated with this phenomenon and did discover that the Moses' sole has a series of small glands scattered just under the skin which can secrete a highly astringent substance which apparently the shark found very unpleasant. Unfortunately, just at the time, her grant funding was running out and she was planning to try to get additional funding to return to study this remarkable mechanism. I don't know whether she did or not, but the indications at the time were such as to suggest that an extract from these glands might turn out to be an effective shark repellent! I hope she got a chance to investigate further.

A final note. Human beings have a strong survival instinct, but sometimes that gets overridden by an overpowering curiosity or perhaps it is merely an underdeveloped cerebral cortex, also known as stupidity, or a third possibility is a recessive gene which causes a select set of individuals, regardless of age, to taste anything that looks remotely edible. Consider some examples. A threatened pufferfish, all puffed up with its spines sticking out prominently, would not incline me to think of it as a potential meal. As it turns out, there are certain parts of the pufferfish which, especially at certain times of the year, can be highly toxic and, unless properly prepared can prove lethal. I, for one, prefer not to play Russian roulette with my food. How did anyone ever discover that oysters are edible? Personally, I'm still not convinced and, of course, in certain places in the world, at certain times, shellfish can become highly toxic to eat when they have been feeding on microscopic dinoflagellates that produce "red tide." And artichokes! How did anyone ever figure out that artichokes are edible? Perhaps somebody thought that they were terrestrial pufferfish.

Humans, long before recorded history, tried virtually everything imaginable as a food source and some of those experiments were tasty and some produced substances that would help relieve various ailments and pains, while others induced states of euphoria. Nature doesn't come with a guidebook and some of the most tempting-looking plants and animals turn out to be lethal. For example, in the mountains here, there is a wide variety of mushrooms, one of which is particularly striking with its bright red cap with white stipples. It is, of course, the notorious Amanita muscaria or fly agaric or deadly Amanita. It is reported, by some of those who survived, to be hallucinogenic, but its toxin is of such a nature that experiment even with small amounts of it can be deadly.

Early humans lived in a world far less comfortable than our own and were plagued by diseases, parasites, insects, and generally speaking, lived in environments that could turn hostile at any moment. To discover that chewing on willow bark could relieve pain was a matter of great significance; to find plants that one could chew and achieve a state of euphoria, a sense of transport to another and more hospitable and desirable, if temporary, state of being, became for many a survival strategy. The accumulation of this lore and its transmission to successive generations became crucial, as did which kinds of thing were edible and which weren't.

Today,there are few educated people who would venture to eat a sea anemone and some anemones turn out to be not only indigestible, but lethal. Yet, even today, people still eat the soft inner parts of spiny sea urchins which primitive man probably learned from watching sea birds pluck them out of the water and drop them from a height onto rocks to smash them open so that they could get at the good parts. Soups are made from bird's nests; some nomadic tribes relish sheep's eyes; some African tribes regard fat, juicy grubs as a delicacy. Civilized people will, of course, have nothing to do with such gastronomic vulgarities—civilized people eat limburger cheese, escargot, and bêche-de-mer. Of course, anything sounds more edible in French. I remind you that escargot, snails, are simply slugs with shells, that bêche-de-mer consists of soft parts of sea cucumbers, and that limburger cheese is the rotting by-products of milk. So, when it comes to food—Chacun à son goût. Each to his own taste. But, please, don't try to eat a sea wasp.

Comments to the author Richard Howey welcomed.

Editor's note:
The author's other articles on-line can be found by typing 'Howey' in the search engine of the Article Library, link below.

Related Micscape articles:

Jan Parmentier's article Attractive But Deadly looks at why some fungi are so poisonous, using three infamous examples.

 

Microscopy UK Front Page
Micscape Magazine
Article Library

© Microscopy UK or their contributors.

Published in the June 2000 edition of Micscape Magazine.

Please report any Web problems or offer general comments to the Micscape Editor,
via the contact on current Micscape Index.

Micscape is the on-line monthly magazine of the Microscopy UK web
site at Microscopy-UK