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A Lethal Land
They bite, they sting, they spit, they spring. On the island continent of Australia, deadly creatures come in all shapes and sizes -- by land and by sea -- as you will discover on the NATURE episode, AUSTRALIA'S LITTLE ASSASSINS.
Ever since Australia broke off from the ancient supercontinent of Pangea more than 200 million years ago, life down under has gone its own way. Australia has scores of unusual life forms, from the duck-billed mammal called the platypus to enormous spiny trees. Included in the menagerie are a remarkable number of animals armed with deadly poisons and lethal teeth and spines. Often, these creatures come in peace: the venom and sharp points are all for defense. Other times, however, they are weapons of attack.
Australia's majestic saltwater crocodiles, for instance, are an obvious threat. Growing 20 feet long and armed with a ferocious mouth of teeth, these reptiles are typically content to feed on fish or birds and mammals that venture too near the water. Every now and then, however, a "croc" makes a run at a boater or swimmer. As one croc-attack survivor on LITTLE ASSASINS notes, the ambush comes as a shock. Before the victim can react, the croc clamps its jaws shut and dives underwater, corkscrewing violently in a bid to drown its victim and rip it in half. Luckily, more than half of Australia's 100 or so croc-attack victims over the last century have survived.
There are other threats along the coast as well. Beachcombers, for instance, might be tempted to pluck one of the petite but beautiful blue-ringed octopuses from a tidal pool. But don't be dazzled, for the blue-ringed has a deadly bite -- and no known cure.
And beyond the surf swim sharks, always a source of fear. Like the crocodile, however, sharks rarely attack people. Indeed, swimmers have far more to fear from jellyfish, those seemingly harmless blobs of jelly that pulsate placidly in the current. But their elegant tentacles rippling out behind harbor a microscopic source of pain: cells that eject sharp, poison-tipped darts when they sense something nearby. Small fish and shrimp can be paralyzed and killed almost instantly, then drawn up into the jellyfish's stomach. For swimmers, the experience can be howlingly painful, with an unlucky few experiencing heart attacks or worse.
Seagoers off Australia's coast may also be surprised by a brightly-colored sea snake. There are about 30 kinds of these snakes in Australian waters, and while they usually aren't aggressive, they still have deadly venom.
On land, the sea snake's scaly relatives also boast fangs that can inject a deadly dose. Indeed, Australia boasts more than 100 kinds of poisonous snakes -- about a dozen of which rank among the most poisonous on earth. Doctors estimate about 3,000 Australians are bitten each year, with several hundred requiring shots of life-saving antivenom, which counteracts the poison. But a few people each year don't make it to the hospital in time and die. (In the United States, about 8,000 people a year receive venomous snake bites, and about six die.)
Victims may also need antivenom to save them from spider bites. Australia is home to more than 40 species of funnel web spiders, for instance, a group of arachnids known for their toxic venom. Some can paralyze a person with a tiny bite. Others may carry bacteria on their fangs that enter the bite wound, causing the skin to die and flesh to literally melt away. Sometimes, the victims don't even know they've been bitten. And for some, there is no known antidote.
Luckily, researchers continue to develop new antivenoms. The work can be tricky -- especially since it often involves "milking" venom from snakes and spiders in order to study its properties. But for those whose lives are saved after an encounter with one of Australia's little assasins, the effort is well worth the risk.
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A Lethal Land
The home of many venomous creatures.
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Venom Rx
Researchers are seeking cures in venom.
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Deadly Creatures
The facts about these dangerous animals.
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Quiz
Take our quiz on Australia's creatures. |
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Resources
Links and books related to the program.
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