And here are our own questions to which we hope you the reader can provide
the answers. So do get those responses rolling in, and don’t
forget to send us any questions that may have been nagging
you over the years… Someone out there may just have
Please send in your questions and answers to ‘YoY’,
C/o The Sunday Times, P. O. Box 1136, Colombo. Sri Lanka.
or email email@example.com.
Remember the success of this column depends on you…
This is your space.
Why does hair sprout out of our ears and nose as we age
(ugh!), when at the same time, it’s falling off the
top of one’s head?
Do plants feel pain? Some close up, if you touch them.
Why do owls hoot with monotonous regularity for long periods
of time. Surely it can't be to attract mice or a mate? (It
must be the ultimate turn-off)
Why do bats get impaled on telephone wires, when every
other flying creature seems to avoid doing so?
Why does tea change colour when you add lemon?
How fat do you have to be to become bulletproof? What would be the
effect on the Earth, if an alien spaceship came and dragged the
In 1994, the New Scientist magazine began publishing
a weekly column called ‘The Last Word’ with questions
and answers on everyday science; some weird, some witty, others
downright wacky. More than a decade later, the column still continues
and today, The Sunday Times launches ‘YoY’ in similar
Readers are requested to send in their questions,
and also answers to the questions that we will publish weekly. As
the New Scientist put it, The Last Word is devoted to the small
questions in life.
Published here are two sample questions and answers
from the New Scientist:
Q: Why do people have eyebrows?
My father has alopecia, so he doesn’t have eyebrows. In warm
weather, sweat runs into his eyes and makes them sore; in wet weather
he has to keep wiping the rain out of his eyes. So your eyebrows
divert sweat droplets and raindrops from running directly into your
eyes. You would be very uncomfortable without them.
Telford, Shropshire, UK
We use our exceptionally mobile eyebrows to communicate
our emotions. The position of the eyebrows emphasises expressions
on the human face, thus giving others an accurate picture of the
individual’s mood. This gives good indication of whether a
person is friendly, or whether they might be dangerous to approach.
Smiles come in many forms, from expressions of
merriment or contentment to leers, smirks and even anger. The position
of the brow, emphasised by the eyebrows, is what gives us a visual
cue to what an individual is really feeling.
The importance of eyebrow position as a guide
to mood was brought home to me, when a friend had Botox injections
in the lines on her forehead and couldn’t raise or lower her
eyebrows. Talking to her became a disconcerting experience –
the bottom half of her face remained mobile, but her eyebrows did
not move. I couldn’t deduce her mood accurately by looking
at her expression, and needed to use other cues, such as her actions
Eyebrows are important in expressing emotions.
Perhaps most important is the ‘eyebrow flash’, a rapid
up-and-down flick of the eyebrows that conveys recognition and approval.
The ability to telegraph friendly intentions from a safe distance
would have had obvious survival value for our ancestors.
Eyebrow signalling of various kinds is widespread
among primates, although only in humans are the eyebrows highlighted
by setting them against bare skin Ed.
Who needs nine lives?
Q: A friend of mine reckons that you can
drop a cat from any height and it will survive unhurt, because its
terminal velocity is lower than the speed at which it can land unhurt.
Can someone confirm or refute this, because kittens in my house
now look strangely at my friend. I’m sure this can’t
be true, can it?
I’m reminded of a study reported in the Journal
of the American Veterinary Medicine Association in 1987 by W. O.
Whitney and C. J. Mehlhaff, two New York vets, entitled ‘High-rise
syndrome in cats’. The study was also summarised in Nature
a year later. Briefly, the authors examined injuries and mortality
rates in cats that had been brought to their hospital, following
falls ranging from between two and 32 storeys. Overall mortality
rates were low, with 90 percent of the cats surviving, a fact that
supports the correspondent’s ailurophobic friend. However,
the study unexpectedly found that the incidence of injuries and
death peaked for falls of around seven storeys, and then actually
decreased for falls from greater heights.
The Nature article presents three main variables
that determine injury and mortality rate – the speed reached
by the moggy, the distance in which said moggy is brought to a stop,
and the area of moggy over which the stopping force is spread. While
concrete streets work in nobody’s favour when it comes to
stopping falling items, cats suffer relatively little injury (compared
to their owners), because they do indeed reach lower terminal velocities
and absorb the shock of stopping so much better. A falling cat has
a higher surface area to mass ratio than a falling human, and so
reaches a terminal velocity of about 100 kilometres per hour (about
half that of humans). They are also able to twist themselves, so
that the impact is spread over four feet, rather than our two. Also
as they are more flexible than humans, they can land with flexed
limbs and dissipate the impact forces through soft tissue.
To answer the paradoxical increase in survival
rates once seven storeys has been reached, the authors suggested
that an accelerating cat tends to stiffen up, reducing its ability
to absorb the impact. However, once terminal velocity is reached,
there is no longer any net force acting on the cat, and so it will
relax, increasing both its flexibility and the cross-sectional area
over which the impact is dissipated once the cat hits the ground.
I’d still keep your friend away from your
kittens, if I were you. Few buildings in your home town of Oxford
are seven storeys high, but there are plenty of rivers about.
Association, Plymouth, Devon, UK
Vets quite commonly see jaw injuries in cats, usually
as a result of their taking too high a leap from a wall - Ed.
I don’t know what the terminal velocity of
the average cat is, but this question did remind me of a joke. Because
cats always land on their feet and toast always lands buttered side
down, you can construct a perpetual motion machine by simply strapping
a slice of buttered toast to a cat’s back. When the cat is
dropped it will remain suspended and revolve indefinitely due to
the opposing forces.
Staffordshire University, Stoke-on Trent, UK
The risks to different animals of taking a fall
were laid out in 1927 by the biologist J. B. S. Haldane, in Possible
Worlds and Other Essays. He wrote, “Gravity, a mere nuisance
to Christian, was a terror to Pope, Pagan and Despair. To the mouse
and any smaller animal it presents practically no dangers. You can
drop a mouse down a thousand-yard mine shaft, and, on arriving at
the bottom, it gets a slight shock and walks away.
“A rat is killed, a man is broken, a horse
splashes. For the resistance presented to movement by the air is
proportional to the surface of the moving object. Divide an animal’s
length, breadth and height each by ten; its weight is reduced to
a thousandth, but its surface only to a hundredth. So the resistance
to falling in the case of the small animal is relatively ten times
greater than the driving force. An insect, therefore, is not afraid
of gravity; it can fall without danger, and can cling to the ceiling
with remarkably little trouble.”