In hot water
Further to Mark Shilton’s letter concerning the 46 000 becquerels of
radioactivity in 20 tonnes of water discharged from the Tsuruga power station
(4 September, p 54),
I can inform him that a lucky Norwegian, with a well in
granite rock, would be drinking groundwater with a natural content of 31 900
becquerels per litre of the isotope radon-222.
It is not the total radioactivity of the water in becquerels which governs
how dangerous that water is, but the half-life of the radionuclide it contains
and the means of exposure. For example, water containing 100 becquerels per
litre of plutonium-239, with a half-life of over 24 000 years, would be far more
radiotoxic than water containing 100 becquerels per litre of radon-222, with a
half-life of less than four days.
Perfect time
Feedback
(4 September) reports that the recent flyby of the Cassini-Huygens
space probe has slowed the Earth’s orbital motion, delaying the start of the new
millennium by one million-millionth of a second! But fear not. For more than
thirty years, time on Earth has been derived from atomic clocks, which are not
affected by changes in the Earth’s orbital motion.
Letter11
Is “Jennifer8 Lee”鈥攖he author of a recent article in The New York
Times鈥攖he first example of someone adopting their e-mail address as
their given name
(Feedback, 4 September)? I think a more likely explanation is
that this person is a fan of the 1970s science fiction film Logan’s Run,
in which the two main characters were Logan5 and Jessica8.
Net loss
Once again, psychologists are having great fun predicting the dire
consequences for victims of “Net addiction”
(4 September, p 19), this time
warning that four hours of exposure each day can lead to mental illness. Aside
from the obvious comment that over four hours a day of “real life” makes me ill
anyway, I wonder if the same predictions were being made when television first
appeared?
Just good friends
Reader Helmut Zarzycki pokes fun at the state of Kansas’s decision to
sideline teaching in evolution, by suggesting that every Kansas school should
have a note saying, “Genesis has no basis in scientific fact and should be read
for entertainment, not guidance”, pinned to the notice board
(11 September, p 57).
Should the same consumer warning be broadcast for New 杏吧原创
articles?
In the same issue, Fred Pearce mentions the Queen of Sheba who “appears in
both the Bible and the Koran as the wife of Solomon” (p 38). I can’t speak for
the Koran, but she certainly doesn’t appear as the wife of Solomon in my Bible,
just as an appreciative good friend.
Insofar as it is translated correctly, no union is even hinted at. What was
that about stretching credulity?
Worst among equals
So Paul Davies and his researchers found that advertising that demeans women
can be harmful
(4 September, p 6). But is it not sexist of the research team to
assume that only women will be affected by demeaning stereotyping?
Surely his study is a trifle out of date, given the growing trend in
advertising for portraying men as brainless, inadequate morons. The research
should be widened if it is to have any validity for the career counsellors and
employers whom he feels should be warned.
Death on ice
Matt Walker’s report
(4 September, p 4) about the discovery of a virus,
tomato mosaic tobamovirus, that had been preserved for up to thousands of years
in the Arctic is timely. I am convinced that smallpox and other infectious
agents are similarly preserved. Many of the victims of smallpox died in the
Arctic and were buried in the permafrost. As global warming melts the permafrost
and exposes these bodies, there is a serious risk that smallpox and other
diseases long thought extinct will return to haunt us.
Side effects
A head-up instrument panel display that taps into pilots’ peripheral vision
is all very well under normal flying conditions
(4 September, p 11). But surely,
under high G forces or reduced oxygen pressure, peripheral vision is the first
thing to go! I can’t help but feel that this new system could lull one into a
false and dangerous sense of security.
Just so stories
Greg Barnett is right to say that “the likelihood that many genetic
attributes have absolutely no advantage or disadvantage” is a well-documented
evolutionary principle鈥攐ne formulated by Darwin among others
(4 September, p 54).
However, neo-providentialism鈥攖he insistence on finding such
“evolutionary functions”鈥攊s rampant today. Just as theologians used to
seek out divine uses for wasps and nettles (handy for rousing humans into
activity), so strange adaptive functions are constantly found for human traits.
Similarly, the flamingo’s pink legs are thought to be camouflage against the
sunset when they are actually due to a diet of shrimps.
Could someone develop a vaccine against this teleological virus?
Seeds of doubt
The assertion that conservation must not become “gardening” is a view so
commonly voiced by conservationists that they seem to be in denial of a possible truth
(4 September, p 46).
Nature conservation, at least in Britain, is
dependent on a range of management inputs such as clearing, grazing, burning and
control of invasive species, which are nearly all designed to compensate for the
disappearance of traditional land uses that provided habitats for species now in
decline. The only difference between this and gardening is that we can cut
vegetation and disturb the ground to encourage seed germination, but we cannot
actually plant that seed.
Traditional conservation philosophy is firmly based on the separation of
human agency from every other process. Ecosystems are “natural” if they are not
affected by any human disturbance, at best “semi-natural” if we have made any
impact on them. A species is native if it arrives by itself, exotic if we carry
it. This sense that nature is other than human seems meaningful to us. But if
you accept the premise that this environmental detachment can translate into a
disregard for nature, then conservation policy makers could be reinforcing the
problems they are trying to combat.
With the bottom dropping out of the world’s biodiversity, it must seem
strange to some countries to see naturalists in Britain debating which sorts of
positive interventions we allow ourselves and which we do not. A rationale that
denies positive human intervention to counterbalance the negative leaves us with
a bleak image of the future. “Gardening” nature could be redefined, therefore,
as stewardship. If we lose some abstract essence because of our presence in the
ecosystem, then it is time to get over that loss because it has already
happened.
Trunk terror
The motive for building “Africa’s largest single ancient monument”, the
10-metre-high ramparts of Sungbo’s Eredo in Nigeria
(11 September, p 38), was, I
believe, quite straightforward. They were not built for spiritual purposes or to
defend against a human enemy, but to keep out elephants.
It is hard for us to appreciate what it was like for farming communities
trying to survive when surrounded by hundreds of elephants before the invention
of modern firearms. It must have been terrifying, life-threatening, and worth
any amount of effort in building ditches and walls to keep them out. In numerous
articles, Richard Barnes from the University of California has described the
conflicts between humans and elephants in the tropical rainforests of West
Africa, and how farmers told him that their forebears lived on the brink of
starvation as their food supply was regularly devastated by elephants. Even
today, elephants can cause persistent damage to crops and drive villagers from
their homes.
All over sub-Saharan Africa there are ramparts, walls (wider than an
elephant’s trunk) and ditches that appear to have little function, especially to
Eurocentric archaeologists who have no experience of the terror and destruction
that can be wrought by pachyderms.
Letter
It is quite likely that the earthworks attributed to Sungbo are no more than
the remains of outlying defences surrounding the old Benin Empire. The complex
political and social organisation of the Benin Empire was based on villages as
political units whose chiefs owed allegiance to the oba (king) of
Benin. This partial autonomy is probably responsible for the number and extent
of the earthworks in the forest lands.
Kidology
Helene Guldberg makes clear that British parents now take more precautions to
protect their children from strangers
(4 September, p 47), and then states that
the chance of a child being killed by a stranger is no greater now than in the
1950s. This means that despite all the extra parental precautions, the number of
children being killed by adult strangers has not been reduced, indicating that
the threat of adult strangers preying upon children has probably increased. The
fact that paedophiles are using the Internet for contacts and information
exchange shows that such people are becoming more sophisticated and efficient,
which supports the idea of increased threat.
Guldberg’s mixing of different dangers was misleading. The chance risks taken
by children during play are significantly different from the risks intentionally
posed by adults who target children. If the child population doubled, most
parents would understand that the percentage of children dying as a result of
accidents would remain about the same. But if the percentage of children being
murdered remained the same, parents would not regard the increased number of
deaths as acceptable. British parents are capable of making a distinction
between the motives, methods and consequences involved when children hurt
children as opposed to when adults attack children.