Pest-free nests
Bryant Furlow’s article on birds’ use of herbal remedies to control nest pests
(22 January, p 36)
explains my problem with sparrows.
I have watched house sparrows nesting under a hot corrugated iron roof carry
in sprigs of yarrow, basil and capsicum raided from my garden. Basil is very
aromatic and may contain “defensive volatile compounds” as yarrow does. The
capsicum was the sweet variety (not hot chilli), but as a Solanum it probably
also contains protective or poisonous substances.
The birds, usually the males, only nipped off the seedlings from my garden
when there were young in the nest. Now that the nestlings have all fledged, they
have stopped and I have planted out more seedlings which the birds leave
alone.
Colours of intent
Red, green and blue are the colours of the Martian flag
(15 January, p 5) not
as a reflection on human optical biology but as a declaration of intent. Red
(Martian rock), green (plant life) and blue (liquid water) are the successive
stages of terraforming Mars, as set out in Kim Stanley Robinson’s epic trilogy
Red Mars, Green Mars, Blue Mars.
After you, Sir
Feedback’s note about the Fire and Explosion Research Group
(29 January)
reminded of an occasion when I was working as a subcontractor at the Royal
Ordinance Factory at Burghfield.
Getting into the place meant a long and somewhat mind-numbing series of
security checks which took at least 45 minutes from first entry to the final
workplace. A moment of light relief was inadvertently provided at one of the
checkpoints by a notice proclaiming in large letters “Personnel carrying
explosives have the right of way”. I don’t think anyone ever thought of arguing
with that.
Y10K bug
I wish to claim the right to name a new computer bug. Rather than calling it
the “Y10K” bug, I declare it as the “PJ10K” bug in honour of my name.
I hereby give Bill Gates 8000 years warning that computer systems cannot cope
with a 5-digit year. Try it on an Excel spreadsheet to see that adding days from
say 25 December 9999 works OK until you turn the new century. From then
辞苍鈥拢辞迟丑颈苍驳.
This may seem trivial at this time, but beware. There is a possibility that
human kind may develop time travel in the next century or two. If our intrepid
time lords scoot off into the future without adequately configuring their
computers for a 5-digit year, who knows what will happen to them?
2nd law reversed
The impossible has happened. My son is turning chaos into order. He is
tidying his flat prior to moving.
This must be an example of reverse time as in Marcus Chown’s article about
looking backwards to the future
(5 February, p 26).
Look at me!
I was surprised that your article on sexual selection by colour
(29 January, p 22)
did not mention the possibility that bright colours in males may also
signify their fitness in evading attack by predators.
Presumably most animals that see each other are often attacked by other
visually adept animals. To survive in such an environment, the brightly coloured
males would need to be agile, fast and alert鈥攁ll good heritable
traits.
These traits would be difficult to display when they are most
needed鈥攄uring attacks鈥攁nd few females would stick around to watch.
Males need to be able to display these traits at a secondary level. Between
males it operates as a dare/double-dare strategy.
It might be interesting to compare brightness of colouring with levels of
predation across species (especially by visually adept species). My hunch would
be that top-level predators and other species with no predators do not use
colour as a signifier of genetic worth.
Running wild
I notice with interest the plan to produce a new series of “organic” hybrid seeds
(29 January, p 12).
I am sure many readers would like to know the details
of the tests that will take place before these random and potentially dangerous
hybrids are allowed into trials.
The similarity of the desired traits to those introduced by the more precise
processes of genetic engineering raises concerns about possible cross-contamination of GM crops.
Target the zones
Image analysis software, which your article says will be used in police speed
traps, has all sorts of interesting applications, from detecting adulterated
rice to explosion and flame analysis
(5 February, p 17).
I understand there’s a problems with patents putting the price up. One method
of cutting the cost is simply not to use these speed traps on motorways, where
accident statistics don’t justify spending a lot of money. Instead, devices are
needed to enforce speed limits in those areas where most fatal accidents
occur鈥攊n 30 mile per hour zones.
A bit of cheek
Just a note on the item about circular breathing among saxophonists
(Feedback, 8 January).
This technique is of course used on other instruments,
most famously on the Australian didgeridoo, but also on the Sardinian launeddas
(see http://sardinia.net/sonus/).
All bagpipes use the same principle for maintaining airflow, with the bag
playing the role of the “squeezable” cheek reservoir. In bellows-blown bagpipes
the bellows take over the role of the lungs.
You closed with a comment suggesting that circular breathing could be used to
cheat in a breathalyser test since it can “deliver clean, pure air into the bag,
largely untainted by alcohol from the bloodstream”. I have my doubts about this.
The air stored in the cheeks and expelled by the cheek muscles must have been
previously inhaled into the lungs.
A few attempts should be enough to convince you that it is impossible to fill
the cheeks with air directly from the nasal passages with the airway to the
lungs closed. There is simply no mechanism for it since the cheek muscles cannot
expand the mouth cavity to suck in air.
Genome fears
If, as your review implies, Barbara Katz Rothman’s book Genetic Maps and
Human Imaginations truly does argue against sequencing the human genome
(29 January, p 48),
then I must argue in its favour.
First, the question of “who we are”: we shouldn’t worry that our
personalities will be reduced down to individual, genetically determined traits,
for the plain and simple reason that we are much more dynamic than that.
Secondly, Rothman’s arguments seem to bend heavily towards fear of eugenics.
But our ethical, moral and common sensitivities are often underestimated when it
comes to considering how our new technologies will be regulated. The fear of the
unknown can be appeased by our gift of reason, care and consideration.
Finally, we will one day be able to ease the suffering caused by
life-threatening diseases. The Wellcome Trust Genome Campus at the Sanger Centre
in Cambridgeshire, for instance, is mapping one-third of the 3000 million bases
of genetic code. One of its projects will try to work out which gene alterations
are responsible for each type of cancer. All the information will be readily
available to help other researchers in their work. It is a worthwhile effort and
one we should be proud of.
Sick maths
I just have to comment on the innovative mathematics in your article on
potted plants and sick building syndrome
(15 January, p 5). You say that 10
plants make no difference to the unusually high levels of formaldehyde in the
air in Portakabins, but that 20 plants reduced the level of formaldehyde from
856 parts per billion to 761 ppb, a difference of 95 ppb.
Earlier in the article you say the WHO’s safety standard for formaldehyde is
82 ppb. You also state that levels in the offices tested ranged from 10 ppb to
78 ppb鈥攁lready below the WHO safety level.
So 20 plants, removing 95 ppb, might reduce the formaldehyde in the air in an
area from a level 15 per cent above the WHO safety standard to a level of zero.
And the conclusion is that this is not “any significant degree”. The data
certainly doesn’t support this conclusion.
African biosafety
The biosafety negotiations are a complex issue with a long history and I
understand the need for simplification
(15 January, p 14). But to say that the
confrontation is one of the US versus Africa only is oversimplification.
I was elected by the “like-minded” group of countries from the South and
negotiated on everybody’s behalf, not only on behalf of Africa. Similarly,
though the suggestion is flattering to me, I can’t take credit for convincing
the 53 member states of the Organization of African Unity to adopt model
biosafety legislation鈥攖hough I might have contributed to that.
African negotiators to the biosafety talks asked us, the Ethiopian
delegation, to prepare draft model legislation. This was later reviewed and
modified into a common African position paper at a meeting of all African
countries. I cannot be credited, as in a mythology of heroes and villains, with
managing the feat of making Africa confront the US single-handedly. At best I
was a catalyst.
Anyway, thanks a lot for turning me into a hero of Africa, and Africa into a
global David.
Letter
Ehsan Masood asks: “杏吧原创s and farmers in the US are among the most
experienced in the world, so shouldn’t Africa be tapping into their
expertise?”
He seems to believe that farmers in Africa have less expertise than US
farmers. That might be true for industrialised, high-input agriculture but it’s
patently false for small-scale farming. Small farmers in Asia and Africa have an
astounding array of crops and cultivation technologies which, when properly
used, easily match the yields of modern industrialised agriculture.
A gene technology which keeps this in mind and is willing to relax on profits
may yet contribute to feeding the hungry.