Issues Magazine

Of Pandas and Peas

By Cary Fowler

They may lack the charisma of megafauna, but plants are the objects of stronger connections with people. Can they cope with climate change?

It was an inauspicious beginning. Days after the international community failed to establish legally binding measures to halt climate change, the United Nations launched the International Year of Biodiversity. Scientists predict that climate change will directly imperil one-quarter of the Earth’s species.

The months that followed have featured stories on charismatic megafauna such as whales, tigers, gorillas and pandas, as well as the diversity of species found in the oceans and tropical forests. Most of all the stories – originating largely from organisations devoted to saving species – included the threat of extinction. The issue of “endangered species” has dominated the biodiversity narrative since the 1980s, when the term entered into common usage.

To many people, “biodiversity” is almost synonymous with the word “nature”, and “nature” brings to mind steamy forests and the big creatures that dwell there. Fair enough. But biodiversity is much more than that, for it encompasses not only the diversity of species but also the diversity within species. It includes not only wild species and their diversity, but domesticated species and their diversity.

It is the diversity within species that keeps species going. This is the diversity upon which natural selection works; the diversity that fuels adaptation and evolution for everything from pandas to peas. Unless we appreciate the critical role that intra-species biodiversity plays in the survival of species, we risk seeing extinction as a numbers’ game – something that happens when the last individual dies.

Extinction, however, is a process, not an event. It effectively occurs not when the last individual dies but when the species loses the ability to adapt successfully. After that it’s just a waiting game for the last individual to succumb. No species gets a free pass.

In the game of life, less diversity means fewer options for change. Wild or domesticated, panda or pea, adaptation is the requirement for survival.

People and Plants

Whether we consciously realise it or not, the biodiversity with which we are most familiar, and the biodiversity with which we have most intimate historical, cultural and biological connections, is associated with food plants. We all know that apples come in red, yellow and green models, and we know some of the varietal names. But how many people realise that there are thousands of distinct varieties of potatoes, tens of thousands of varieties of beans, hundreds of thousands of types of wheat, and even more of rice?

This diversity, this cornucopia of genes, has arisen and persisted in large part because of the ancient and ongoing tie between people and plants. Farmers and more formally trained plant breeders use the diversity found in wheat and other crops to improve the yields, disease and pest resistance of the varieties in use today.

The process of varietal improvement is continuous. The bread you eat today is undoubtedly made from different varieties of wheat than 25 years ago, as new varieties have been continuously developed for higher yields and to stay one step ahead of ever-evolving pests and diseases.

Nevertheless, when we think about biodiversity, we rarely think about food. The word “biodiversity” doesn’t appear in Culinary Artistry, an interesting book I recently read about food and cooking traditions. Yet the book, of course, is all about the interplay between cultural and biological diversity.

What is it that makes one cuisine distinct from another? Which foods and spices are strongly associated with a particular cuisine? What makes Thai food “Thai” as opposed to Italian? It doesn’t necessarily have to do with where the crops were originally domesticated. So many key ingredients are immigrants!

Spicy Thai dishes with chillies and peanuts employ ingredients of American origin. Italy’s pasta and China’s noodles depend on wheat that was first domesticated in the Near East. Nordics love their (Andean) potatoes. And quintessentially Brazilian ingredients such as black beans, garlic, lime, rice and scallions are historical imports, with the possible exception of the beans.

Spices have travelled far and wide too, fuelling an international trade that stretches back millennia. Today, cumin, from the upper Nile area, figures prominently in cuisines from sub-Saharan Africa, the Caribbean, India, Indonesia, Mexico, Middle East, Morocco, Spain, Thailand and Tunisia.

The number of crops we use for food is impressive enough, but the diversity within those crops is particularly notable for both agronomic and cultural reasons. Like other biodiversity, however, it is endangered.

Plants and animals are not waiting for the next IPCC report to document global warming. Hundreds of scientific articles document the movement of wild species in response to climate change. But the disturbing fact is that many aren’t moving fast enough, and can’t. Others simply have no corridors of escape. All are potential climate change road kill.

Agricultural crops face a similar dilemma. As with pandas and many other wild species, the maize and sorghum varieties grown by subsistence farmers in Africa cannot and will not easily relocate. And staying where they are is hardly an adaptive strategy that inspires confidence. Even if such crop varieties were to survive, what would become of the farmers hit with devastating drops in production due to climate change?

Seed banks, with their vast collections of crop diversity, constitute a cultural corridor, a bridge through time that will help enable crops to adapt to climate change. The biodiversity that seed banks protect may not inspire our empathy as easily as pandas, but its loss would be catastrophic for many, many species.

The International Year of Biodiversity is now coming to a close. Charismatic biodiversity will be celebrated. Less charismatic biodiversity will be eaten.

Beginnings are often messy. Perhaps it matters little whether the international community chooses to celebrate crop diversity, but it profoundly matters that the international community takes action to conserve it.