the cultural beliefs and practices of people using
them. This coded information interacts with the
environment through plant physiology and human
behaviour and leads, ultimately, to the end state of
plant phytochemistry (nutritional value and toxicol-
ogy) and human nutritional and health statusFigure 1.Nutritional adaptation and biocultural evolution.When these mechanisms interact with one another
in a positive manner, there is a distinct biocultural
advantage. Nowhere is this more apparent than in
the use of maize. In the Americas, maize flour is
usually limed prior to making tortillas. Magnesium
and calcium salts are added, releasing niacin which
enhances the quality of protein. Phytate is neutral-
ized, making iron and zinc bioavailable (Katz et al.,
1974). African cultures, who do not lime their maize
flour, are at a biocultural disadvantage. For example,
Kuito, an area in Angola where maize forms a large
proportion of the diet, is an area of endemic niacin
deficiency (Golden, 2002).- The loss of biocultural diversity and dietary
diversity
The close relationship between agricultural biodiversity,
cultural diversity and dietary diversity is no more
apparent than in farming communities in developing
countries. However, over the last century there has
been a loss of agricultural biodiversity and associated
traditional knowledge, particularly for food plants,
with a corresponding reduction in dietary diversity.
Many attribute these losses to intensive agriculture,
the nutrition transition and environmental pressures
such as climate change (Goodland, 1997; Johns and
Eyzaguirre, 2006; Purvis et al., 2009). Since the green
revolution, a focus on providing high energy and
high protein foods of plant origin to an expanding
global population has been the main driver of
intensive agriculture. While succeeding in this, it has
pushed lesser known agricultural biodiversity into
kitchen gardens, fallow fields and field margins,
communal land, grasslands, orchards, and roadsides,
at risk from agricultural expansion, road widening,
hedgerow removal, overgrazing, overharvesting,
herbicides and other non-traditional agronomic
practices. Climate change is likely to become an
increasingly significant threat, particularly for
narrowly adapted endemic species (Millennium
Ecosystem Assessment, 2005; Jarvis et all., 2010).
The nutrition transition is also playing its part, as
the desire for “modern” westernized diets causes a
shift from diverse traditional diets, relatively low in
energy and high in plant diversity, to modern diets,
high in energy and low in plant diversity. The stigma
often associated with traditional diets not only
supports and encourages the intensification of agri-
culture, but also exacerbates the trend towards a
global obesity epidemic.
Although the main focus of global agricultural
research remains the provision of calories and plant
protein, pressures on our current global food system
mean that the intensive agricultural practices
developed over the last century may not be sustainable
in the future, leading many to advocate the use of
lesser known or underutilized plants from traditional
food systems as part of the solution (Johns and
Eyzaguirre, 2006; Bharucha and Pretty, 2010).
Conserving such plants, and the cultural diversity
that supports them, requires a holistic approach,
based on an understanding of plant and human
interactions.- The conservation of food plant diversity
The CBD cross-cutting initiative on biodiversity for
food and nutrition includes an operational objective
to conserve and promote the wider use of biodiversity
for food and nutrition.In situconservation and
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EvolutionPlantsPeopleCodesDNACultureStrategiesPhysiologyBehaviorStatesPhytochemistryNutritional
Status