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5. Why are some people left-handed?
About 10 per cent of the population is left-handed, and it
seems to run in families. The cause, therefore, seems obvious:
genetics. However, identical twins, who have identical genetic
blueprints, aren’t necessarily both left-handed or right-handed.
This would appear to disprove the theory that being left-handed is
inherited.
Even at birth most babies tend to move one arm, usually the
right, more than the other. Some scientists believe that the use of
left hand or right hand is a result of the baby’s environment. Most
children can be trained to use and to prefer the right hand for any
activity.
6. Why do we sleep?
On average we spend a third of our lives sleeping, but no one
really knows why. The most popular theory is that sleeping gives
the body and brain a chance to recover from the stresses of the
day. But beyond this vague statement, we don’t know what this
recuperation consists of. Warm-blooded species, including
humans, birds, and mammals, seem to need more sleep than cold-
blooded creatures such as fish and reptiles, so there is a possibility
that we sleep in order to save energy. Sleep deprivation produces
hallucinations.
7. Why is yawning infectious?
This is a tough one. No one even knows what purpose
yawning serves at all. But we do know that fatigue, boredom, and
anxiety can trigger off a yawn.
Like crying and laughing, yawning is a variant of normal
breathing. Yawning is a reflex action, not under conscious
control. The mouth opened wide and you take a longer, deeper
breath than usual. Yawning momentarily raises the heart rate,
forcing more blood to the brain. One theory is that yawning
makes you more alert by making you breathe in more.
Yawning isn’t infectious in the clinical sense of the word.
8. Does nature allow time travel?
Amazingly, there is nothing in the known laws of physics
to prevent us from zooming off into the past or future. Exactly
how one would build a time-machine is anyone’s guess, but
many scientists have a bigger worry – paradoxes such as killing
your mother before she gave birth to you. Maybe Nature has a
clever way of getting round these. Or maybe there is an as yet
undiscovered barrier to time travel. But just think! If at any time
in the future time travel becomes possible, then time travellers
are with us now!
9. How will the universe end?
This depends on how much matter exists in the cosmos. If
it exceeds the so-called critical density, gravity will bring the
current cosmic expansion to a half and trigger a contraction or
implosion billions of years from now. Alternatively, the
universe may expand for ever. After decades of research,
astronomers still don’t know precisely how much matter exists
in the universe and so cannot predict accurately how the
universe will end. The consensus, however, is that the cosmos
will expand for ever.
10. Where do all the odd socks go to?
Open any sock drawer and you’ll find odd socks. Theories
about what happens to them range from disappearing down
black holes in the universe to being eaten by washing machines.
breath than usual. Yawning momentarily raises the heart rate,
5. Why are some people left-handed? forcing more blood to the brain. One theory is that yawning
makes you more alert by making you breathe in more.
About 10 per cent of the population is left-handed, and it Yawning isn’t infectious in the clinical sense of the word.
seems to run in families. The cause, therefore, seems obvious: 8. Does nature allow time travel?
genetics. However, identical twins, who have identical genetic
blueprints, aren’t necessarily both left-handed or right-handed. Amazingly, there is nothing in the known laws of physics
This would appear to disprove the theory that being left-handed is to prevent us from zooming off into the past or future. Exactly
inherited. how one would build a time-machine is anyone’s guess, but
Even at birth most babies tend to move one arm, usually the many scientists have a bigger worry – paradoxes such as killing
right, more than the other. Some scientists believe that the use of your mother before she gave birth to you. Maybe Nature has a
left hand or right hand is a result of the baby’s environment. Most clever way of getting round these. Or maybe there is an as yet
children can be trained to use and to prefer the right hand for any undiscovered barrier to time travel. But just think! If at any time
activity. in the future time travel becomes possible, then time travellers
are with us now!
6. Why do we sleep?
On average we spend a third of our lives sleeping, but no one 9. How will the universe end?
really knows why. The most popular theory is that sleeping gives
the body and brain a chance to recover from the stresses of the This depends on how much matter exists in the cosmos. If
day. But beyond this vague statement, we don’t know what this it exceeds the so-called critical density, gravity will bring the
recuperation consists of. Warm-blooded species, including current cosmic expansion to a half and trigger a contraction or
humans, birds, and mammals, seem to need more sleep than cold- implosion billions of years from now. Alternatively, the
blooded creatures such as fish and reptiles, so there is a possibility universe may expand for ever. After decades of research,
that we sleep in order to save energy. Sleep deprivation produces astronomers still don’t know precisely how much matter exists
hallucinations. in the universe and so cannot predict accurately how the
universe will end. The consensus, however, is that the cosmos
7. Why is yawning infectious? will expand for ever.
This is a tough one. No one even knows what purpose 10. Where do all the odd socks go to?
yawning serves at all. But we do know that fatigue, boredom, and
anxiety can trigger off a yawn. Open any sock drawer and you’ll find odd socks. Theories
Like crying and laughing, yawning is a variant of normal about what happens to them range from disappearing down
breathing. Yawning is a reflex action, not under conscious black holes in the universe to being eaten by washing machines.
control. The mouth opened wide and you take a longer, deeper
