Q: Do scorpions drink water? If they do, where do they go to drink water? What do scorpions eat? Ryan, Fountain Hills, Arizona
A: Depending on where they live, some scorpions drink water; others don't. These creatures, closely akin to spiders and mites, are survivors. They evolved an excellent body plan over 400 million years ago, and have seen little reason for major change since. The 1500 living scorpion species have adapted, though, to fill every conceivable habitat niche: from arid African deserts to snow-covered Himalayan mountains over 12,000 feet (3660 m) high.
Those that live in grasslands, forests, intertidal zones, rain forests, mountain highlands and caves drink from streams and pools. In captivity, they will drink regularly from wet wads of cotton wool left in their cage, the International Wildlife Encyclopedia says.
The desert is a different matter. Some scorpions, living in deserts near the sea, drink condensed fog.
Most desert species of scorpions don't drink water at all. Instead their bodies separate water from the food they eat.
On the morning of Aug. 13, 1989, a thick ocean fog rolled over the Namib Desert of southwest Africa. Two biologists (Gary Polis from Vanderbilt University in Tennessee and Mary Seely from the Desert Ecological Unit of Namibia) spent forty minutes watching a 3-inch (8-cm) Parabuthus scorpion drink fog dew. The scorpion pushed her tan body slowly through the yellow grasses. She moved her small, sharp, claw-like mouthparts (chelicerae) over the grass stems, obviously "collecting and drinking water."
Most desert species, however, don't drink water at all. Instead their bodies separate water from the food they eat. In fact, scorpions can only digest liquid food. Once they get water, they keep it. Several layers of a waxy substance coat their exoskeleton, and trap the precious water.
Scorpions mainly eat insects and spiders, but will "prey upon anything they can overpower within striking distance", including centipedes and other scorpions, Jonathan Leeming writes in Scorpions of Southern Africa. The larger scorpions also occasionally eat small lizards, snakes and mice. Most scorpions lurk outside their lairs at night, and ambush their prey. Moreover, some scorpion species can wait out lean times, not eating at all for more than a year.
Further Reading:
- Scorpions glow in the dark, WonderQuest
- Imbibition of precipitated fog by Gary A. Polis and Mary K. Seely, The American Anarchnological Society
- Scorpions, Jonathan Leeming
- International Wildlife encyclopedia, edited by Maurice Burton and Robert Burton
Q: Almost everyone that I talk to believes that the far side of the moon is always dark (hence, the saying, "dark side of the moon"). Nobody believes me when I say the far side is completely lit by the sun, when the moon is in New Moon phase, (that is to say dark). Can you help me enlighten the folks out there? Kerry, Inyokern, California
A: The Moon rotates at the same speed as it orbits the Earth. So, in the 27 days it takes the Moon to go around Earth, the Moon also spins about its axis one full revolution. That's why we always see the same face of the Moon.
The side of the Moon we don't see is called the "dark" side. However, the word "dark" is a matter of semantics. It's an early term meaning "unknown" or "unseen," like calling Africa the "Dark" Continent. We, on Earth, never see the "dark" side of the Moon from Earth, but suppose you live on Moon, as some of us soon may. Then you will experience a day: the Sun will rise and shine on the moonscape, move across the black lunar sky and — 27 days later — set below the Moon's horizon. Click here to see the Sun shine on the far (but not dark) side of the Moon. Then click "animate" for a lively show. Courtesy of Chris Dolan and the University of Wisconsin, Madison.
Further Reading:
- Does the Moon rotate? WonderQuest
- Why does the Moon look so large on the horizon? WonderQuest
- Moon phases, Keith's moon page
- An animation showing how the Earth and the Moon orbit the Sun, Collins
- A calendar showing the moon phase for each day of the current month, StarDate Online
April Holladay lives in Albuquerque, New Mexico. Her column, WonderQuest, appears every second Monday of the month on globetechnology.com. To read April's past columns, please visit her site. If you have a question for April, visit this information page.
