The terms “atmosphere” and "biosphere" are surely familiar to you. But what about the “ethnosphere”?   

The ethnosphere, a term coined by Wade Davis, is “the sum total of all thoughts and intuitions, myths and beliefs, ideas and inspirations brought into being by the human imagination” (Davis, W. et al. (eds) Book of Peoples of the World: A Guide to Cultures, National Geographic Books, 2007). 

Policy assessments that aim to understand how humans interact with ecosystems have been dominated by “western” viewpoints. However, this is at odds with our planet’s cultural diversity: indigenous societies occupy one quarter of terrestrial lands and over 7,097 indigenous languages are spoken on Earth. Knowing that 2019 would be the International Year of Indigenous Languages and that many languages are in danger of disappearing, we were moved to reflect about the erosion of our ethnosphere, and whether science assessments and decision-making related to sustainability have drawn on the entire kaleidoscope of human thought. 

To explore these ideas, my student Zoe Dennehy and I carried out a quantitative literature review to assess how well indigenous knowledge about plant services (e.g., food, medicine, construction) has been studied across biological (ecosystems) and cultural dimensions (indigenous groups). We furthermore examined how the distribution of plant services may influence assessment completeness. To do so, we focused on New Guinea: although less-studied than other tropical regions like Amazonia, New Guinea is just as astonishing. It is the largest and most biodiverse tropical island in the world and more languages are spoken there than anywhere else on Earth.

New Guinea supports some of the world's most biodiverse forests. Photo: Rodrigo Cámara-Leret.

Example of literature records about plant services that were compiled for the study. Source: Holdsworth, D.K. 1977. Medicinal Plants of Papua New Guinea. South Pacific Commission

After 12 months of databasing 488 references, we were eager to analyse the data. This phase coincided with finishing Andrea Wulf’s biography of Alexander von Humboldt: not interested in classifying for its own sake, Humboldt sought to find hidden links and explored the interconnectedness of life. Humboldt’s collaboration with artists to show plant distributions in the Andes, Canary Islands and the Himalayas exemplifies his holistic vision in science and is one of his many great legacies. To celebrate the 250^th anniversary of Humboldt’s birth, we collaborated with a wonderful artist to show how information gaps in indigenous knowledge are distributed along New Guinea’s ecosystems. In a ‘Humboldtian’ way, we escaped traditional office spaces, met at art museums, bounced ideas along London’s busy streets, and enthusiastically worked on many sketches. Ultimately, the artist produced a wonderful piece that became Figure 1 of the paper. 

Paintings of Humboldt, Chimborazo and his Naturgemälde. Source: Wikipedia.            

In the 19^thcentury, Humboldt drew inspiration mostly from male scientists. However, in the 21^stcentury we are fortunate that women have a greater voice in science and Deborah Rabinowitz's article on “Seven forms of rarity” was a major inspiration to us. Her theoretical framework discussed why some plant species are much less common than others on the basis of geographic range, habitat specificity and local abundance. We applied it to study rarity in plant services as our currency of measurement and found that like the common property of rarity in species assemblages, most plant services also exhibit high rarity (see Figure 4 in the paper).

The ideas of Humboldt and Rabinowitz still inspire us because we can read their written works. By contrast, the ability of indigenous groups to share knowledge is rapidly diminishing as their languages go extinct. The deterioration of the atmosphere and biosphere is featured constantly in the news, yet the erosion of our ethnosphere is seldom mentioned. How can we open communication channels to amplify indigenous voices so their insights about ecosystems and their properties are heard by policy makers? How can we draw on the entire kaleidoscope of human thought? 

The ability of indigenous groups to share their rich body of knowledge is rapidly diminishing as their languages go extinct. Photo: Rodrigo Cámara-Leret.