A study conducted by an international research team headed by Lounès Chickhi, a CNRS researcher and a ground leader at the Instituto Gulbenkian de Ciência, has raised questions about the general version that tropical ecosystem destruction is mainly caused by human activity. The study findings propose for reconsideration of the effect of local people on their environment.
The golden-crowned sifaka (Propithecus tattersalli) inhabits the forests of the Daraina region, in northern Madagascar. (credit: Lounès Chikhi, IGC)
The study results, reported in the Proceedings of the Natural Academy of Sciences journal, have demonstrated that significant reduction in the population of golden-crowned sifaka, which are inhabitants of the Daraina region in northern Madagascar, was a result of pre-human effect. Moreover, by studying satellite and aerial images of the Daraina region, the research team confirmed that forest coverage in the region stayed unaffected over the past six decades, thus eliminating any strong impact of local people on the environment.
Hence, based on historical and paleontological records, the study results strongly recommend that the present condition of the Daraina region is caused by pre-human climatic changes. These changes might have played a role in the expansion of open landscapes in the north of Madagascar and subsequent decrease in the population of the Golden crown sifakas, which are tree-dwelling inhabitants.
Using remote-sensing data such as satellite and aerial images and genetic data that provides insights into significant population expansion and reduction events, the research team explored the controversial and long-standing question in conservation biology: to differentiate between the impact of natural factors and humans on ecosystem changes. The study findings provide insights to conservationists, evolutionary biologists, ecologists, and climatologists.
Chikhi informed that the study findings shed light on the significance of representing regional differences in conservation projects. These results have demonstrated that human presence is not the only reason for biodiversity loss. Conservationists must find solutions for sustainable resource management with the help of local communities instead of separating them from their environment.