STRANGE BUT TRUE- Dead snakes: They're riskier than you think


Q. What's quite likely the most surprising deadly snake of the venomous lot?–B. Kidd

A. A rattlesnake isn't the answer but rather a dead rattlesnake! Amazingly, a rattlesnake can still strike an unsuspecting human even if it's been dead for as long as 30 minutes, says Jearl Walker in The Flying Circus of Physics. In fact, numerous people have made the mistake of reaching for a dead snake to remove it from their property, only to find its fangs buried in their hand and the deadly venom delivered. 

What these victims didn't know is that pits between each eye and nostril of a rattlesnake serve as sensors of thermal radiation. For example, when a mouse triggers these sensors, a reflex action can cause the snake to strike and inject its venom, even on a moonless night since the process does not require visible light. The thermal radiation from a human hand can cause the same reflex action even if the snake has been dead for a while because the snake's nervous system continues to function. As one snake expert advised, if you must remove a recently killed rattlesnake, use a long stick rather than your hand. 

Q. One of the most beloved and popular of ancient Olympic events was the hurling of the discus, with the winner awarded the copper object for its metallic value. The 2 kilogram (4.4 lb.) disci today are generally made of steel and wood. What are a few interesting paradoxes concerning the discus throw?– D. Cathlete

A. Paradox #1: A flying-saucer-shaped discus will stay aloft longer and travel farther if thrown into a wind rather than with the wind, as verified in wind tunnels, says Vincent Mallette in Science of the Summer Games. This is true because of aerodynamic lift associated with the oncoming air against the angled object. A rule of thumb is that a 25-mph headwind will add about 25 extra feet to the throw. But too strong a wind can upset the spin orientation, actually sacrificing distance. 

Paradox #2: While Olympic records set by runners and jumpers make note of assisting wind speeds, no such asterisk attends discus throws. Paradox #3: A well-thrown discus in tropic latitudes will go an inch (2.5 centimeters) farther eastward than westward, due to the rotation of the Earth, an example of the Coriolis force which causes hurricanes to turn counter-clockwise in the Northern Hemisphere. That's one scientific tip that isn't in the coaching manuals. 

Q. Weird newspaper contest: Choose a number from 0 to 100 and send it in; the winning entry will be 2/3 of the average of all entries, the prize $10,000. What number would you guess?–M. Lynch

A. If all guesses are random, then the average should be about 50, making 33 (2/3 of 50) a good guess, says Mark Buchanan in The Social Atom. But what if others are thinking along the same lines. Then maybe you should guess 22, or 2/3 of 33. Of course, you can follow this reasoning indefinitely, ultimately leading to a guess of zero! Yet oddly, if everyone chooses zero, then all entries are exactly right, since 2/3 of zero is zero. When this contest was actually staged in London, a few people did choose zero and quite a few chose 33 or 22. The overall average turned out to be 18.9 and the winner had chosen 13. Concluded Buchanan: "A rational economist would have been a certain loser– which is neither rational nor very smart."  

Interestingly, we all face choices of this sort every day. For example, driving to work in the morning you may try to avoid traffic by choosing a road that others won't be taking. But countless others are trying to do the same thing so there is no clear rational solution– unless you can read minds. 

Q. Gold, as you may know, is malleable (can be pounded into sheets), ductile (drawn into wires) and virtually indestructible. In what sense is gold "green" and in what sense is it not? Also, where can most of the metal be found these days as reserves, reservoirs and otherwise?–S. Bassey

A. Gold is eco-green in that windows in some apartment buildings are coated with it to help reflect sun in the summer and retain heat in the winter, says LeeAundra Temescu in Discover magazine. However, getting the metal is far from green since gold mines spew cyanide into waterways and nitrogen and sulfur oxides into the air. "In 2000, a cyanide spill at a Romanian mine made the local water for 2.5 million people undrinkable."

As for gold reserves, the U.S. has the world's biggest hoard. But if ornamentation is included, India takes the title–over 20 percent of the gold used decoratively worldwide is in the thread of Indian saris. Yet the largest reservoirs of gold aren't on the surface of the Earth but rather in the oceans–an estimated 10 billion tons. However, as Temescu points out, "Unfortunately, there is no practical way to get it out." 

Send STRANGE questions to brothers Bill and Rich at