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 name sea wasp is misleading
because the creature isn't actually a wasp or insect at all. It is a
jellyfish (Chironex fleckeri).
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 (check
it out).
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. Makes sense. 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. Hmmm. 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 an 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.
NEW!!
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