Copyright 2003, all rights reserved
Tree ghosts, twin chicks, ďdullĒ number
My family and I were camping in Shawnee National Forest in Illinois. My brother,
hunting firewood, knocked down a dead tree teeming with ants. That night, the
wood glowed in the dark. In the day, the moist wood appeared white but, at
night, it glowed neon green ó clearly visible 40 feet away in the pitch black
dark. Did chemicals from the ants cause the glow? ó Dave, Indianapolis,
Honey mushroom fungi glow in the dark [Tom Volk, University of Wisconsin -
A: Chemicals, yes, but not from the ants. You saw a fungus, called foxfire,
glow a cold chemical fire, like a fireflyís light. The fungusí body grows inside
the wood and eats it.
Foxfire rots wood by digesting it and extracting nutrients. That's why we
often see mushrooms in or near dead trees. The mushroom is the fruit. The
feeding body grows in the wood and the surrounding soil. Foxfire glows and
thereby makes the inside of a rotting tree glow.
We donít know why fungi glow. Perhaps to release excess energy or waste
"Foxfire may be any of several fungi, but, almost always, itís the honey
mushroom (Armillaria mellea) and related species," says Tom Volk, biology
professor at the University of Wisconsin - La Crosse. This honey-colored
mushroom is common all over the United States and found on every continent but
The best time to see foxfire (and it is a treat) is in late summer or fall.
University of Wisconsin -
La Crosse: Tom Volkís fungi
WonderQuest: How fireflies glow
Have two chickens ever hatched from one egg? You know, like twins. ó
Jennifer, Houston Texas
Twin chicks usually hatch from double-yolk eggs but can
occur from a single yolk. [Corel]
A: Yes but rarely. The two chicks are always tiny and usually hatch from a
double yolk egg. Often only one embryo survives and sometimes neither does. The
egg isnít big enough to house two normal-size chicks so often one dies.
Ordinarily they arenít identical twins but fraternal. "A double yolker forms
when one egg follows another down the shoot a little too closely and they both
get wrapped in the same shell," says Liz Armstrong of the Classroom @ the Coop.
Texas A & M
University: Poultry Q&A
What is the smallest "dull" number? J. R., New Jersey
An Indian stamp issued in 1962 to commemorate the 75th anniversary of
Ramanujan's birth. [India Postage]
A: It's early in the afternoon of a pleasant fall day.
The phone rings. It's J. Richard Gott, Princeton astrophysicist.
"Iíve got a question for you," he says. "What is the smallest "dull" number?"
"A smallest dull number?" My voice rises, wondering
what in the world...
Gott relates an incident. In 1917, a mathematical genius, Ramanujan,
lay ill in a London hospital. His friend, G.H. Hardy, came to visit. Hardy
remarked that his taxi number (1729) was dull.
"No," Ramanujan replied, "itís an interesting number; it is the smallest
number expressible as the sum of two cubes in two different ways."
1729 = 13
+123 = 93 +103
Zounds! I thought. To
be able to recognize such a fact upon hearing the number.
Gottís reaction, however, was to wonder what is a dull number.
And he had an answer to his own question: A number is dull if no one uses it.
Earlier he had checked Google, repeatedly. Whatís the smallest number with no hits on the Internet?
Eventually, he got close. The number 13,965,320 returned only
a single hit. The next number returned no hits. He gave me the number; it is:
13,965,320 + 1.
I'm expressing it this way so Google won't find it, because of me.
Thatís his answer. Can anyone find a smaller one? Or,
University of St Andrews, Scotland: Srinivasa Aiyangar Ramanujan
(Answered Oct. 17, 2003)