News

Q: My daughter brought the following website to my attention: www.genpets.com/faq.php . It purportedly will market "genetic pets" in the near future. Could this all be true? Or is it a very elaborate joke? Akhlesh, University Park, Pennsylvania

A: The website elaborately markets "living, breathing mammals" with "blood, bones, and muscle" created through "zygote micro injection." According to the site, these pets "are grown in assisted breeding lab farms" and make wonderful pets.

Is it true? No. Is it a very elaborate hoax? Not exactly. The site is a protest about where genetic engineering may be taking our society. Buried deep in the Genpets site is a link to the sculptor's portfolio and a description of the "pets." Adam Brandejs creates the "genetic" pets from plastic, latex rubber, polyurethane foam, microchips, motors, paint and paper. He sells the robotic creatures for $1,200 (U.S.), and displays them in the V-Gallery in Basel Switzerland, and elsewhere.

"I'm not against bioengineering," he says. "I'm hesitant toward where and how and by whom the technology will be used."

Further Reading:

• We do not understand cloning. How does it work? How is it done? WonderQuest
• FAQ, Genpets
• The art and sculptor of Adam Brandejs

Q: Do sap trees blow up in the winter? And how? Brendon, Fairborn, Ohio

A: On April 1, 2005, All Things Considered warned their listeners about maple trees with sap flowing within: "An untapped tree is a time bomb ready to go off." Sounds of an enormous explosion then drowned out the speaker's voice. But — the program was an April Fool's joke.

Sap trees don't blow up in the winter, at least due to the pressure of the sap. Sap pressure is somewhat less than root pressure, and root pressure is only about two tenths of an atmosphere. Thus, the pressure that sap can exert is too small, compared with the tree's wood strength, to rip apart a tree.

Barks of trees (maple included), though, have been known to burst in extreme cold, and crack like a gunshot, as plummeting temperature causes the wood to contract.

The winter of 1968 to '69 was bitterly cold in north central Washington State. Wally and Shirley Loudon lost half their orchard that winter.

"We saw 47 below on our porch, and we didn't look again," Shirley told Good Fruit Grower Magazine. "I would hear these bangs and I blamed it on the house expanding or contracting, or whatever, from the cold, but it was the trees exploding. It was the bark bursting, and you could hear it." Half their trees died.

Also, trees can explode if lightning strikes them. The current surges through sapwood, boiling sap and water in the conducting channels. The resulting steam can blast off bark and wood. An older tree, rotting at the core, can explode. The conducting path for the lightning lies not in the sapwood but in the core's moisture. In this case, the return path of the lightning can crack the tree along its length and literally blow it apart.

Further Reading:

• Why don't untapped maple trees explode? PhysicsForums.com
• Tree, nature's lightning rod, West Virginia Lightning

Q: I've heard that cows can't blink. Is this true? Robert, Edinburgh, Scotland

A: That's not true; cows blink just as we do.

By the way, sharks can't blink. They have three eyelids. The upper and lower lids don't move, so the shark can't blink. They can and sometimes do slide the third inner lid (a thin, tough, translucent membrane) horizontally across each eye to protect the eyes, especially while eating.

Further Reading

• Farming: metabolic problems in cows 2farm.co.nz
• Do sharks blink? San Diego Natural History Museum

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 informational page.