"The punchline is, that if you are interested in conserving biological diversity, excluding the Indigenous people who likely helped create that diversity in the first place may be a really bad idea," said Larry Gorenflo, professor of landscape architecture, geography and African studies, Penn State. "Humans are part of ecosystems and I hope this study will usher in a more committed effort to engage Indigenous people in conserving localities containing key biodiversity."

Gorenflo, working with linguist Suzanne Romaine, Merton College, University of Oxford, UK, looked at 48 localities in Africa designated by the United Nations Education, Scientific and Cultural Organization (UNESCO) as Natural World Heritage Sites. These sites host "globally important natural or combined natural and cultural resources," they report. This paper was placed online as an unedited manuscript in January 2021 ahead of final online publication in April 2021 in Conservation Biology.

They analyzed geographic information system data on Indigenous languages in these areas and found that 147 languages overlapped with the UNESCO sites. Indigenous languages occurred in all but one of the Natural World Heritage Sites examined.

"The Namib Sand Sea desert in Namibia is a pretty dry area," said Gorenflo. "Kind of desolate, with wonderful sand dunes and natural features, but so harsh that there is no one living there as far as I know."

But in all the other Natural World Heritage Sites in continental Africa and on nearby islands, Indigenous people not only live, but, to some extent, manage the environment in which they live and have been doing so for a long time.