26 | New Scientist | 8 June 2019
Putting population
on the policy agenda
25 May, p 24
From Iain Climie,
Whitchurch, Hampshire, UK
Population growth poses
problems, but the solutions are
far from simple. For example,
China’s one child policy has
misfired because of a preference
for boys, and its population is
now disproportionately elderly.
Even if we were to halt world
population at its current level,
it may not help much when it
comes to resource depletion.
Medical advances are most likely
to prolong the lives of those with
high-impact, well-off Western
lifestyles. Poorer countries
aspire to these lifestyles, and it
is often estimated that to provide
everyone with this would use the
resources of multiple Earths.
Add in an economic system
that boils down to “make more
money, buy more stuff” and the
outlook appears bleak for future
generations and the natural world.Young people are more
energetic away from home
25 May, p 9
From Mary Z. Fuka,
Gainesville, Florida, US
Adam Vaughan’s article
implies that older people
use more energy, but the study
quoted only looks at residential
energy consumption. This doesn’t
include energy consumed outside
the home – at work, school,
while commuting, shopping or
during any other activity that
many people in the US under
60 engage in. People over the
age of 60 spend more time at
home because they are more
likely to be retired and to be
less physically capable.Surgery is risky enough –
don’t do it over 5G
13 April, p 8
From Sam Edge,
Ringwood, Hampshire, UK
Yvaine Ye reports on doctors inChina using 5G internet to do
surgery from afar. A video data
stream delivered by a mobile
phone signal will still have
travelled most of the way
between the cities of Guangzhou
and Gaozhou over conventional,
land-based copper and optical
fibre cables.
No matter how slight the signal
delay in the final, short 5G wireless
link, it will still be at the mercy of
the rest of the signal path – it is
the whole journey that counts, not
just the 5G part. Every router and
switch the data stream passes
through – and there may be quite
a few – adds to this, and the extra
delay may depend on how loaded
the network is at the time. It is
possible to prioritise crucial
traffic, but there is no widely
agreed mechanism for this,
as far as I know, especially
between national carriers.
In any case, I should hope
that an operating theatre that is
used for very tricky procedures
that need the help of a more
experienced surgeon elsewhere
would have a fixed line network
connection with plenty of
redundancy built in to guard
against power failures and otherproblems. Using a mobile phone
connection in this case strikes me
as unnecessarily risky.Smartphones were a
luxury NASA didn’t know
18 May, p 25
From Dave Holtum,
Bath, UK
Richard Webb’s comment that
“Apollo missions were launched
on little more computing
power than is found inside
a smartphone” somewhat
underestimates progress in
computing speed since 1969.
Smartphones are more than
100 million times faster than an
IBM 360 mainframe, which was
probably the fastest computer
that NASA had. Apollo engineers
wouldn’t even have dreamed of
such computing power.Could pollution explain
high twin rates?4 May, p 15
From Anthony Wheeler,
Mackay, Queensland, Australia
You report a high incidence of
twins in a small village in India.
If this isn’t a statistical anomaly,and if the incidence of identical
twins isn’t increased, I suspect
the involvement of an anti-
oestrogenic environmental
pollutant. In veterinary practice,
decreasing the availability of
oestrogen in the hypothalamus,
for example by using the
oestrogen antibody drug
Fecundin, increases the number
of ova shed by sheep and the
lambing rate. In humans, the
effect would be increased
incidence of fraternal twins.The editor writes:
The researchers did report testing
the water and diet in a previous
paper, but that wouldn’t rule out
a pollutant from another source.We’ve got a way to go when
it comes to wind and solar
18 May, p 15
From Perry Bebbington,
Kimberley, Nottinghamshire, UK
The graph accompanying your
report on renewable energy
illustrates how far we are
from having enough storage
capacity to cover times when
there is little or no wind or solar
generation. There is a big dipViews You r le t te r s