DOESN'T ALWAYS YIELD CORRECT ANSWERS
by Whit Gibbons
August 6, 2006
can be viewed as a reminder to us that the world is full of surprises.
Also, it is salutary for would-be experts to be proved wrong from time
to time. If you think I am remembering, and justifying, a time when I
was wrong, you are correct.
I had been
asked this question. "Could the small, white eggs the size of mothballs
in the wooded area in my backyard be the eggs of a venomous snake?"
I asked for
more information. Were they laid in an old stump, under a log, underground?
And how many were there?
lying in leaves on the ground."
that they were not eggs of a rattlesnake, cottonmouth, or copperhead,
as all North American pit vipers are live-bearers; they do not lay eggs.
Also, they were not the eggs of a coral snake as the caller was outside
the geographic range of the species. So, whatever they were, they would
not hatch into anything venomous. I proclaimed that they were probably
lizard eggs based on the description. The true answer was revealed a few
the answer to another question about venomous snakes required less guesswork.
Q. I will
be giving a speech on poisonous snakes to my Toastmasters group. I have
found no answer to this question: How do lists get created that rank snakes
in order according to their deadliness? Do a bunch of snake experts sit
around and reach a consensus based on personal experiences and readings?
opinions of people who deal with snakes certainly come into play, as well
as medical records from hospitals. But such rankings are also based on
scientific research. The U.S. Navy published a book called "Poisonous
Snakes of the World" in which the venom yield and lethality of 40
venomous species were compared. Mice were the victims in a series of tests
to determine the amount of venom required for a lethal dose to a mouse.
Because of the variability of response to venom, the determination was
based on how much venom needed to be injected into an individual mouse
before half the mice in the sample were killed. In other words, what was
the lethal dose for 50 percent (known as the LD50) of the mice? Drop-for-drop
the Australian tiger snake in the cobra family was 47 times more deadly
than an eastern diamondback rattlesnake. One of the sea snakes was 4 times
deadlier than the tiger snake. After a point, it probably doesn't much
matter, as many other factors can influence the seriousness of a snakebite.
Health of the victim, site of the bite, and how much venom, if any, is
injected can be particularly important.
about how venom potency is ranked was relatively straightforward compared
to the question about the small, white eggs. Two days later we got the
answer to that one. My wife answered the phone, chuckled, and said to
me. "Turns out they found out what the white eggs were."
that would be?" I asked, feeling like I was being set up.
what kind of lizard did you think it was?"
one of the blue-tailed skinks. Don't tell me they were coral snakes. That
would be a geographic range extension."
were mushrooms! They pushed on up through the leaves." The caller
and my wife had clearly had a good laugh over that one, so I had to respond.
"I asked her where the eggs were. She didn't say they were sitting
out in the open."
you said she said they were in the leaves. Of course, mushrooms grow up
through leaves. I guess that's the way they hatch." More laughter
at my expense.
I knew it
would be a long reach for a recovery if I merely noted that at least I
had been right about their not being snake eggs. Instead, I said that
I hoped she had told the caller not to eat the mushrooms until she knew
for sure what kind they were. True, they would not hatch into venomous
animals, but they just might be poisonous.
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