Journal of Experimental Botany, Vol. 54, No. 390, pp. 2003–2006, September 2003
DOI: 10.1093/jxb/erg239
Plant culture: thirteen seasonal pieces
September – ideas of nature
Nicholas H. Battey
What is nature? Three views are presented, each associated with the month of
September. The French republican calendar symbolized the break with the past,
the new months being named after plants and the seasons. In this case, nature
stood for freedom from the ancient regime. The designer Charles Rennie
Mackintosh took his inspiration from the natural world, here illustrated by
‘The Harvest Moon’. For him, nature (particularly plants) gave an insight
into the realm of eternal beauty. The third view of nature is illustrated by
research related to fruit ripening. ‘Cosuppression’, discovered early in studies
with transgenic fruit, is now understood as a variety of RNA silencing. This is
a natural mechanism by which plants control levels of gene expression using
non-coding DNA. Nothing, apparently, is without function. All is directed to
the one driving purpose of biological nature: evolutionary fitness. Freedom,
beauty, fitness: three concepts that reflect the preoccupations of the times.
Plants seem to have been scattered profusely over the face
of the earth like the stars in heaven, so that the lure of
pleasure and curiosity should lead men to study nature.
J-J Rousseau (1777)
On 21 September 1792, three years after the French revolution had begun
with the storming of the Bastille, the National Convention met for the first
time and abolished the monarchy. A new calendar was constructed to begin
from the following day. The months were based on the seasons:
Vendémiaire (22 September–21 October)
Brumaire (22 October–20 November)
Frimaire (21 November–20 December)
Nivôse (21 December–19 January)
Pluviôse (20 January–18 February)
Ventôse (19 February– 20 March)
Germinal (21 March–19 April)
Floréal (20 April–19 May)
Prairial (20 May– 18 June)
Messidor (19 June–18 July)
Thermidor (19 July–17 August)
Fructidor (18 August–21 September)
wine harvest
mist
hoar frost
snow
rain
wind
shoots
flowers
fields
harvest
heat
fruits
Journal of Experimental Botany, Vol. 54, No. 390, © Society for Experimental Biology 2003; all rights reserved
2004 Battey
There were many reasons for the introduction of this new calendar. It
represented a break with the past and the inequalities of the old regime. It
justified the new beginning by its connection to the natural world, the
Republic being founded on the autumn equinox; as the Committee of
Public Instruction put it, ‘The sun passed from one hemisphere to the other
on the same day in which the people, triumphing over the oppression of
kings, passed from a monarchical government to a republican government’.
It would free the people of France from the chaotic mixture of customs that
constituted the traditional calendar; time would now begin on 22
September 1792, rather than at the birth of Christ. And, finally, the
republican calendar was rational, reflecting the spirit of the Enlightenment,
and announcing the victory of science over religion.
Beneath all this was an idea of nature, derived in large measure from JeanJacques Rousseau, who, although he had died 11 years before the
revolution, had been enthusiastically taken up by the revolutionaries. He
believed that man was fundamentally good, part of a beneficent natural
world, and that both man and nature
had been corrupted by society. His was
an optimistic account because the
mistakes of the past could be corrected
and a more equal and free society
achieved. The irony is that devotees of
Rousseau, such as Robespierre, carried
out their slaughter with the aim of
realizing his vision of a benign natural
world.
‘The Harvest Moon’ by the artist and
architect Charles Rennie Mackintosh
expresses a different idea of nature (Fig.
1). The picture is influenced by the
Symbolist movement of the late 19th
century. The harvest moon is the full
moon within a fortnight of 22
September, and the name originates in a
‘farmer’s year’ that predates the
adoption of a formal calendar. The angel
figure against this moon thus contrasts
pagan and Christian world-views, and
relates to the wider autumnal theme of
decline and replacement. But all
Mackintosh’s work reflects a deeper
conviction, that nature gives an insight
into the realm of eternal beauty. He thought that in using the forms of
nature, particularly plants and flowers, the artist should strive ‘to convince
the world that there may be – there are things…more lasting than life’. This
is the Platonic idea of eternal forms, to which the natural world aspires and
according to which the ultimate reality is an abstraction.
Fig, 1. The Harvest Moon,
Charles Rennie Mackintosh.
Painted 1892. From Glasgow
School of Art Collection
(Photo: Copyright Glasgow
School of Art)
Plant culture: September 2005
The third view of nature, a scientific one, is as abstract as Mackintosh’s, as
idealized as Rousseau’s, yet it is completely practical. Ripening fruit, used to
symbolize autumn in the foreground of ‘The Harvest Moon’, have yielded
insight into the strange and marvellous world of RNA silencing. In some
early studies with transgenic plants, transformation with a sense copy of a
gene was unexpectedly found to cause silencing of the endogenous gene.
This was the case with genes for petal colour, as well as with a gene
associated with wall softening during fruit ripening.
Detailed investigation of these curiosities has revealed that RNA silencing is
not just an artefact thrown up by transgenic studies, but occurs as a natural
mechanism within plants. This discovery has converged with evidence of
equivalent phenomena in other organisms. The research has therefore led, via
a circuitous route, to a new picture of RNA behaviour. RNA transcripts, as
well as being translated into proteins, can, if double-stranded, be degraded to
small signalling molecules that direct targeted breakdown of homologous
mRNA. It appears this mechanism arose as a way of defending the plant
genome against invasion by RNA viruses and other molecular parasites that
produce double-stranded RNA during their replication. But it has been
adopted by the plant genome for its own regulation: recent evidence
indicates that intergenic (‘non-coding’) regions of DNA encode small RNAs
with the potential to regulate gene expression. That is, small RNAs can
function as epigenetic regulators, with suggested involvement in processes as
diverse as flowering and nitrogen metabolism.
Much is still to be discovered, but the most remarkable aspect of this
remarkable story is the extension of the function of ‘non-coding’ DNA.
This function-finding is central to a scientific ideology that accounts for
nature only in terms of evolutionary fitness, in a society that glorifies
ruthless business fitness. Our idea of nature conforms to our beliefs. The
French republican calendar esteemed the natural world and associated it
with freedom. Charles Rennie Mackintosh saw eternal beauty in nature, and
extolled its aesthetic virtue. Our science imbues all nature with a fitness
function, discovering with glee the detail in the detail, as in RNA silencing.
It reflects perhaps our purpose-hungry selves.
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2006 Battey
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The author
Nicholas H. Battey
Plant Science Laboratories, The University of Reading, Whiteknights, Reading
RG6 6AS, UK
Fax: +44 (0)118 3788160. E-mail: [email protected]
Plant culture: thirteen seasonal pieces