This is not a question that Gorenflo et al. (2012) ask in their widely publicized PNAS article on the “co-occurrence of linguistic and biological diversity”. They seem to subtly presuppose a positive answer, but one wonders about the precise implications of this.
The contribution appeared as a regular scientific paper in the high-profile Proceedings of the National Academy of Sciences of the USA, and it contains the usual trappings of such a paper: maps, charts and statistics. Like many PNAS papers on readily accessible topics, it was widely reported on in the media (e.g. here and here). But the major finding is neither new, nor do the authors have an explanation: They demonstrate that the 35 biodiversity hotspots and the five biodiversity wilderness areas have a higher concentration of languages than would be expected by chance. That linguistic diversity and biodoversity are correlated has been known for quite some time, and the term biocultural diversity has gained currency in some circles (see Maffi 2005 for a review), but the reasons for the correlation are unclear (see Asya Pereltsvaig’s post on Languages of the World). Gorenflo et al. mention several explanations proposed by others, but they do not discuss them seriously and end up saying that the reasons are “complex and appear to vary among localities”. So in other words, the correlation is spurious?
The main point of the paper seems to be an agenda for action: The authors are suggesting that the conservation of endangered species and the conservation of endangered languages should be seen as a single enterprise:
“it may be impossible to achieve large-scale conservation of species and the ecosystems that contain them without incorporating resident languages and the cultures they represent into biodiversity strategies” (Gorenflo et al. 2012, last sentence)
Even if the processes that shaped the similar geographical distributions of biodiversity and glottodiversity may have been different, “similar forces currently appear to be driving biological and cultural/linguistic homogenization”. This force is of course the “expanding industrialized global economy”, which represents “risks to languages and their associated cultures”. So it’s primarily the desire to protect species and languages from the global economy that drives this “scientific” article. This is made very clear by an article in the Huffington Post by Russell Mittermeier, one of the four authors of the study. He notes that “efforts to conserve nature and ensure the integrity of human cultures can go hand in hand”. In other words, if nature is conserved, then human cultures will remain isolated (because the people do not have roads and airports etc.), but also vice versa: If people are not part of the global economy, they will not destroy their surrounding biodiversity:
“certain cultural systems and practices, represented by speakers of particular indigenous and nonmigrant languages, tend to be compatible with high biodiversity” (Gorenflo et al., p. 6)
Russell Mittermeier is president of the American advocacy group Conservation International, another coauthor of the article is also a member of that organization, and the article seems to have been timed to appear just before the Rio+20 summit. This kind of mixture of political and scientific issues may not be so unusual in the natural sciences, but as a linguist, I was struck by it.
And I wondered whether for some members of the “small groups which are vulnerable to external pressures in a rapidly changing world”, the global economy appears not just as external pressure, but also as an opportunity to get out of their poverty and marginalization. Even in Germany, the German language is rapidly getting weaker, as the business and science elite is turning to English in their desire to be global players. Why should others who are in far greater need of expanded opportunities be more faithful to their ancestors’ languages?
In any event, there is apparently no evidence that biodiversity conservation efforts have had any effect on language conservation, or vice versa. Language conservation has been effective where the speakers have been able compete on global markets (e.g. Catalan, Hebrew), while the longer-term effectiveness of other measures has yet to be demonstrated. We can close off entire natural areas and let the animals and plants alone, but presumably nobody wants “linguistic nature reserves” that no outsiders are allowed to enter.
In this context, it is probably useful to pause and think more deeply about the current endangerment discourse in general – see the working group at the Max Planck Institute for the History of Science on Endangerment and its consequences. It seems clear that there is always a lot of ideology behind efforts to conserve, and it is good to be aware of it.
I agree that biodiversity and language are strongly related.For this justification Ethiopia is a best example.Come and visit Ethiopia if you are interested biodiversity
One approach to understanding the connection between linguistic and biological diversity is to invert the question. Instead of asking why high-density areas correlate, it’s useful to ask why both biological diversity and linguistic diversity have plummeted everywhere else. After all, these biocultural hotspots are much closer to the original or ‘natural state’ of languages and biospheres. In terms of explaining this correlation, these hotspots are in a way the least interesting, because they haven’t yet been exposed to the processes leading to a drop in diversity. What is needed first are explanatory theories of language shift and biological decline. Whatever aspects are common to both will be the beginnings of an explanation for the interesting correlation between biological and linguistic diversity.
As far as a theory of language endangerment goes, I’ve written on this a little, and I believe that many of the causes I’ve suggested are potential causes of biological decline as well: