This week, Collected Wisdom grabs its deerstalker hat and Meerschaum pipe while it ponders the Case of the Disappearing Corpse. Watson, the violin, if you please …
THE QUESTION: Shelley Nickerson-Allen of Lincoln, N.B., says that if she steps on an ant at the family cottage and doesn't dispose of it right away, another ant soon comes along, picks the dead one up and carries it off. "How do they know it's there?" she asks. "What do they do with the body?"
THE ANSWER: As to how they know it's there, Bob Johnston of Pitt Meadows, B.C., says ants lay down a scent trail or pheromone track that other ants follow. As the dead ant is probably on this track, that's how they find it.
As to how they know it's dead, Rob Laird of Lethbridge, Alta., says: "In the 1950s, renowned myrmecologist (ant researcher) E.O. Wilson demonstrated that ants' corpses emit a number of chemicals, such as oleic acid, that nest mates use to diagnose death. Dead ants are taken to a refuse pile to ensure colony hygiene."
Mr. Laird points out that in Dr. Wilson's 1994 autobiography Naturalist, he describes an early experiment on the phenomenon.
"To test this conclusion about the simplicity of ant behaviour I asked, finally, what would happen if a corpse came to life? To find out, I daubed oleic acid on live workers. Their nest mates promptly picked them up, even though they were struggling to get free, and carried them to the refuse pile. There the 'living dead' cleaned themselves for a few minutes, rubbing their legs against their body and washing the legs and antennae with their mouth parts, before venturing back to the nest. Some were hauled out again, and a few then yet again, until they became clean enough to be certifiably alive."
Thus, if CW might summarize: In a manner of speaking, the ant at Ms. Nickerson-Allen's cottage is taking its comrade off to the ants' graveyard.
THE QUESTION: Why do new tires have all those little hairs on them? asks Henry Ko of Montreal.
THE ANSWER: When a tire is moulded, a certain amount of air is trapped between the tire and the mould, writes Richard King of Aurora, Ont.
"There are small holes in the mould that allow this air to escape as the tire expands to fit the mould," he says. "Once all the air is gone, a little rubber flows into the holes and gets cured (along with the rest of the tire). When the tire is taken from the mould, these 'hairs' pull out of the air channels."
- Why do sleep-deprived people get shadows under their eyes? Philippa Hunter of Toronto wants to know.
- Tonya Bassler of St. John's writes: "Why do we hunch up our shoulders when we're cold? Does this actually keep us warmer?"
- "My cat regularly uses an outdoor wooden support as a scratching post, over time producing a mass of ugly splinters," writes Derek Hayter of Brampton, Ont. Why don't the splinters hurt the cat's paws?
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