Scorpions: Friend or Foe? (Grades 3-6)
A scorpion can control how much venom it produces in its stinger.
Lorenzo Prendini, a scientist at the American Museum of Natural History
Scorpion researcher Lorenzo Prendini has had more than his share of death-defying experiences. Surprisingly, most have nothing to do with the scorpions he studies.
Scorpions can be found all over the world, but desert areas hold the greatest variety. "The places where scorpions can be found tend to be very harsh environments," says Prendini, a scientist at the American Museum of Natural History in New York. Risks like exposure to dangerous tropical diseases and deadly snakes are just part of the job. Prendini has braved them all on the way to discovering more than 70 new species of scorpions.
Scorpions are sting-happy creatures with a bad reputation. A relative of spiders, these eight-legged arachnids can grow up to 20 centimeters (8 inches) long and have two threatening, lobster like claws.
But unlike most invertebrates, female scorpions give birth to live young and are protective mothers, says Prendini. "We found a scorpion in Mexico that arranges the babies on her back and transports them around, like passengers on a bus," he says. Some scorpions look after their young for up to two years.
Scorpions are probably best known for their frightening tails, which are topped with sharp, venom-filled stingers. They use their venomous stingers to catch food and to defend themselves if they are threatened.
Scorpion stings cause roughly 800 human deaths a year around the world. But the venom of most scorpions is harmless to humans. Out of 1,500 known scorpion species, only approximately 25 are dangerous. Elderly people and children are most at risk. "Healthy adults will probably survive scorpion stings by even the most venomous species," says Prendini.
Scientists have recently discovered that the venom of some scorpion species can actually help humans. One scorpion's venom has been found that can treat brain cancer. Chemicals in the venom kill cancer cells, but leave a person's healthy cells unharmed.
Prendini says this type of research has just begun. "I have no doubt that as we learn more about scorpion venoms, we will discover more uses," he says.
A STINGING BLOW
Another reason Prendini risks life and limb to study scorpions is that the creatures hold clues about the environment around them. Tough-looking scorpions are actually very sensitive to environmental changes. If the scorpions in an area begin to get sick or die off, it's a clue that the environment is in trouble.
Human activities like farming and mining have changed scorpions' environment in many areas. As a result, several scorpion species are at risk of dying out. That's a sign that many other organisms are at risk too.
For both scorpions and humans, the stakes are high. We have a lot to gain from studying species, even the ones with a bad reputation, says Prendini.-By Elizabeth Carney