How long can scorpions live without food or water?

There are around 2,000 known species of scorpions, but fewer than 40 have venom that can kill humans. See more pictures of arachnids.
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On a clear night, you may be able to look up and spot a curved string of stars nestled between Libra and Sagittarius. As the Greek legend goes, Artemis, the goddess of wild animals, sent a scorpion to kill the hunter Orion. For that reason, the constellation Scorpio was placed strategically in the heavens on the opposite end of the horizon from Orion's constellation, as if eternally chasing him.

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Mentions of scorpions stretch back into some of the oldest know myths because the species has survived for an estimated 450 million years. Their distinct body shape and pointed stinger have earned scorpions a negative reputation for millennia, commonly associated with evil and chaos. Ironically, of the 1,300 known scorpion species scattered across the globe, fewer than 40 of them possess venom powerful enough to kill a human. Those dangerous species are found in the Middle East, Africa, Mexico, South America and India. But that doesn't mean that scorpions don't inflict their fair share of pain. An estimated 5,000 people die from scorpion-related causes every year [source: Leeming].

The scorpion is a member of the arachnid family and is closely related to spiders, mites and ticks. Arachnids have four pair of legs and two body segments: a cephalothorax and abdomen. Their bodies are coated in an exoskeleton made of a substance called chitin. A peculiar quality of that external shell makes scorpions easy to spot in the dark. Because of an unknown chemical in the chitin, if you shine an ultraviolet light on a scorpion at night, its body will fluoresce, or glow. Its tail is divided into five segments (ending with the venomous stinger), and on the opposite end of its body, the scorpion has a set of crablike pincers called pedipalps it uses to grasp and crush prey.

But the scorpion doesn't have to put its sturdy set of armor to use very often to capture meals. Like the patient fisherman who sits calmly for hours on end for a bite on his line, the scorpion is a master of waiting for food.

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Diet of a Scorpion

Scorpions can live without food or water for more than a year.
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You can find scorpions in almost every habitat in the world: tropical rain forest, savanna, desert, mountains and grasslands. They mostly hide out under rocks and logs to preserve energy and stay cool. Scorpions have multiple eyes like other arachnids, but they have poor eyesight. To make up for that, scorpions have special sensory feelers called pectines on the underside of their abdomens. Pectines can detect scent trails left by other scorpions as well as the surrounding air movement.

Although they're nocturnal, scorpions generally don't go out of their way to search for food. Instead, they are opportunistic feeders that wait for their food to come to them rather than wasting energy actively hunting. What types of food do they lay in wait for? Scorpions are carnivorous arachnids, like spiders, that primarily feed on other insects and even other scorpions.

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A scorpion may display its cannibalistic tendencies even during mating rituals. After depositing a spermatophore outside of his body for the female to absorb through her genitalia, the male scorpion must crawl away quickly. If not, he may end up as his mate's dinner [source: Angier]. If this behavior sounds familiar, you're correct. Female black widow spiders are also known to prey on their male suitors.

But what happens when food doesn't come their way? With an adaption suited to their isolated living conditions, the scorpion possesses an incredible ability to slow its metabolism to a third of that in similarly-sized insects. During lean times, the scorpion's metabolic rate is the lowest of all invertebrates [source: Lighton et al]. At that pace, eating one insect can sustain a scorpion for a year. In order to turn down their metabolism, scorpions engage in minimal activity. In fact, in order to maintain that sluggish metabolic rate, many scorpions spend 92 to 97 percent of their lives completely inactive, sort of like an extensive state of hibernation [source: Leeming].

­Even when the scorpion's body has slowed down to barely functioning, it can still quickly snap into action to catch a meal. But when a scorpion attacks its prey, it doesn't immediately gobble it up. Rather, it first excretes enzymes through its fangs, or chelicerae. Those enzymes then break down the insect matter before it enters the scorpion's body in an example of external digestion. That way, the scorpion maximizes the nutrients that it sucks out of its meal without squandering the energy involved in internal digestion.

This lethargic existence works out well for the scorpion, which is able to survive as long as 25 years in a variety of climates. That makes it the longest-living arachnid species. Yet, given its Spartan diet, a scorpion that reaches its peak age may enjoy just over a couple dozen meals in its lifetime.

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