74 Science & technology The EconomistSeptember 28th 2019
2 tested positive for the Huntington’s-caus-
ing mutation, meaning that her child has a
50% chance of having it too.
Initially the case was struck out, on the
grounds that letting it go to trial would risk
undermining doctor-patient confidential-
ity. But in 2017 that decision was over-
turned. The appeal court concluded that
situations could arise where a doctor had a
duty of disclosure to a patient’s relatives,
and that preventing the trial on the
grounds that it posed a threat to the doctor-
patient relationship was therefore not nec-
essarily in the public interest.
In Britain doctors have a duty under
common law to protect a patient’s confi-
dentiality, and are released from that duty
only with the patient’s consent. However,
professional organisations such as the
General Medical Council recognise that
breaching patient confidentiality may
sometimes be necessary, in circumstances
where not doing so would probably result
in death or serious harm. Identifying such
situations is left to doctors’ judgment.
The German case is in some ways the
mirror image of the British one. Unlike in
Britain, in Germany the right not to know
genetic information is protected in law.
Nevertheless, in 2011 a doctor informed a
woman living in Koblenz that her divorced
husband—the doctor’s patient—had tested
positive for hd. This meant that their two
children were at risk of the disease.
She sued the doctor, who had acted with
his patient’s consent. Both children being
minors at the time, they could not legally
be tested for the disease, which, as the
woman’s lawyers pointed out, is currently
incurable. They argued that she was there-
fore helpless to act on the information, and
as a result suffered a reactive depression
that prevented her from working. A district
court initially rejected the woman’s case,
but that decision was later overturned. In
2014 the German Federal Court of Justice
handed down a final judgment, once again
rejecting her case.
Both cases, then, test a legal grey area
and their outcomes will be examined with
interest by lawyers in other jurisdictions. If
the right to know is legally recognised in
Britain later this year, that may remove
some uncertainties, but it will also create
new ones. To what lengths should doctors
go to track down and inform family mem-
bers, for example? Will trust break down
between patients and doctors if confiden-
tiality is no longer watertight?
It is the law’s job to balance these rights
for the modern age. Some worry this is an
impossible task, but it has to try. When the
law falls behind technology, somebody of-
ten pays the price, and currently that some-
body is doctors. As these two cases demon-
strate, they find themselves in an
impossible predicament—damned if they
do, damned if they don’t. 7Two years ago the solar system was
visited by ‘Oumuamua, an asteroid from
interstellar space. It was the first such
body observed, but now a second alien
object (pictured alongside) is in
astronomers’ sights. 2I/Borisov is a comet,
rather than an asteroid. The distinction is
that, warmed by sunlight, 2I/Borisov has
developed a temporary atmosphere called
a coma. This difference also affects the
way it is named. Unlike asteroids, comets
are called after their discoverers. The new
visitor was first reported by Gennady
Borisov, a Russian amateur observer, on
August 30th, and was officially named on
September 24th. Its closest approach to
the sun will be on December 7th, after
which it will disappear back into the
cosmic tracts whence it came.A traveller from an antique landA
frican bush lilies are demanding
plants. To thrive, they need dappled
shade—for they are sensitive to full sun-
light—and well-drained soil. They are
therefore patchily distributed, growing
only in microclimates where these condi-
tions pertain. That means their seeds are
likely to do best if they germinate near the
plant that bore them. Too near, though, and
they will compete with that parent for re-
sources. Somehow, a way needs to be ar-
ranged for seeds to be carried the optimum
distance from their parental plants. And
Ian Kiepiel and Steven Johnson at the Uni-
versity of KwaZulu-Natal, in South Africa,
think they know how it happens.
Plants are masters at manipulating ani-
mals into assisting their reproduction. One
way this happens is that the seeds of many
species are just the right size and shape to
endure passage through the alimentary ca-
nals of the animals that swallow them.
When they eventually end up as part of a
dung pile, they are thus far from home. The
bush lily’s predicament, however, suggest-
ed to Mr Kiepiel and Dr Johnson that it was
not in the plant’s best interest for animals
to swallow its seeds in the first place.
Closer examination of those seeds sup-
ported that notion. They lacked the protec-
tive layers seen in seeds of the sort that are
swallowed. They were also laced with lyco-
rine, a toxin that, depending on the dose,
causes vomiting, paralysis or death. This
led Mr Kiepiel to wonder whether the fruit
themselves were edible. To this end he ex-perimented on himself and found that they
were. Though not particularly pleasant to
his taste, lily-fruit flesh had a vague sweet-
ness to it which he suspected might be at-
tractive to other mammals. He did find
also, however, that the seeds tasted ghastly.
A mere nibble of one was enough to release
an awful astringent flavour that lingered
on his palate for hours, regardless of any at-
tempt to wash out his mouth.
In light of this experience, he and Dr
Johnson set up movement-sensitive cam-
eras at three bush-lily colonies. As they re-
port in Biotropica, over the course of a hun-
dred days these cameras took photographs
and videos of samango monkeys coming to
the plants and devouring their fruit.
Often, when feeding, such monkeys fill
their cheek pouches with fruit, which they
then consume later, within the safety of a
tree. In this case, though, the cameras re-
corded the monkeys gorging themselves
on the fruit while next to the lilies, and only
rarely storing fruit in their pouches. Why is
not clear. But significantly, the cameras
showed that the monkeys were, straight
away, spitting out the seeds of every fruit
they fed on.
This habit of spitting out seeds suggest-
ed that the monkeys might be distributing
them just far enough from their source to
keep competition between parents and off-
spring at a minimum. To check this, the re-
searchers visited two of the sites, collected
as many spat-out seeds as they could find,
and measured those seeds’ distances from
their probable sources—nearby plants that
had been fed on. Those distances averaged
63cm at one of the sites and 66cm at the
other. This is exactly far enough to avoid
competition while remaining within the
microclimate. In the case of African bush
lilies, then, it seems that evolution has op-
timised their reproduction by embedding
noxious seeds inside tasty fruit, and letting
the monkeys do the rest. 7Lilies monkey around with their fruit
and seeds to ensure their propagationReproductive ecologySpit it out