What Makes the Sea Wasp so Deadly?
There are many creatures on this earth that are quite deadly to humans. The deadliest of all, of course, being other humans. Perhaps, what poses the greatest threat to our lives are creatures we can't even see - microbes. These are the microorganisms we usually call germs or cooties, the ones that make us sick. By and large, disease-causing germs are responsible for the largest number of human deaths every year. But what we're talking about here are the venomous creatures; those whose bodies manufacture toxins that can be rubbed off, ingested (swallowed), or injected into another, causing severe illness or death. Just to name a few, there's the poison dart frogs of the Costa Rican jungles, stonefish, cone shells, the black mamba snake, and even a tiny octopus that lives in tropical waters. When creatures are rated for the "deadliness factor" there's a couple of measures that are taken into account:
1) How many people an ounce of the creature's venom can kill
2) How long it takes you to die from the venom after being bitten, stung, or stuck
In both cases the grand prize winner and world-record holder is the creature known as the sea wasp, or marine stinger. The venom from a single creature can kill up to 60 adults! Over 100 people have been killed by the stings from a Chironex fleckeri and many more have been stung, but lived. Get stung badly enough by one and you could be dead within four minutes. The name sea wasp is misleading because the creature isn't actually a wasp or insect at all. It is a jellyfish. The "bell" of this box jelly can get as big as a basketball with up to 60 tentacles hanging down as long as 15 feet, which is pretty good sized jelly. Not as big as the world-record jellyfish, though.
Silent Stalkers
Sea Wasps, or box jellies, are not aggressive. They don't have to be. For jellyfish, they are pretty fast swimmers (up to 5mph), dangling their long tentacles in the surf behind them until something, usually a fish, gets caught in their practically invisible tentacles. That's where all their nematocysts (stinging capsules contained within cells called cnidocytes located along the tentacles) are located. (Most people who have been stung are Aussies who were swimming in the surf along with the jellies and never even saw the tentacles.) The poison is used to kill their prey as close to "instant" as possible in order to prevent a struggling victim from thrashing their delicate tissues. Then they can take their time devouring their meal without risking injury to themselves.
Deadly Toxins
What's really amazing is how the stinging cells work. They're little tiny poison darts that are buried inside the flesh of each tentacle (like the sweat glands in your skin), along the entire length. They're triggered chemically, by contacting the surface of human skin or the scaly skin of a fish. Scientists have captured box jellies and put them in tanks in the laboratory. Simply by pouring alcohol into the tank they caused the stinging cells to react and release their venom. This means that if the jelly's tentacles don't come in contact with the chemicals on human skin, the nematocysts won't respond and you won't get stung!
Simple Fix
Turns out, something as thin and flimsy as women's nylon pantyhose worn over the skin will prevent the jellies from stinging. Aussies have known about this trick for years. You'll catch totally cool Aussie Lifeguards wearing women's pantyhose over their arms and on their legs. It may look funny, but it can prevent them from suffering agonizing pain and can even save their lives.
Not everyone who has been stung by a Sea Wasp has died, but those who didn't may have wished they had. The sting from a box jelly is said to be excruciatingly painful. It can cause nausea, vomiting and breathing problems. The Aussies have developed a box jelly antivenom (something to counteract the toxic effects of the jelly's venom). Doesn't do you a whole lotta good if you got stung so badly while you were out in the water and then couldn't even make it back to shore. But, you really need to get tangled up good (contacting at least 10 feet of tentacle) in order to experience its ultimate effect - death.
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