Linguistic diversity hotspots
Languages can be study using similar tools as we use for biological organism, because languages, like species, have their geographic distribution, they have variability, they evolve with time, they show divergence and extinction processes. In fact there are phylogenetic trees and networks of languages  similar to those we build for understanding species evolution. In addition, a recent paper show that the hotspots of species diversity also co-occur with hotspots of language diversity , in such a way that highly biodiverse areas accounting for 24% of Earth's land surface contain ca. 70% of the world's languages. However, the reasons of this link is not yet well understood. Are the factors that generate linguistic diversity the same to those that generate biodiversity? Is the linguistic diversity a consequence of the biodiveristy? Nearly 60 percent of the languages in high biodiversity regions, like Amazonia and the lowland forests of West Africa, are spoken by fewer than 10,000 people; more than 1,200 of those languages are spoken by fewer than 1,000 people. So cultural diversity, as biological diversity, is threatened. It is worth mentioning the recent online collaborative effort trying to preserve samples of endangared languages .
 Diversity of languages, jgpausas.blogs.uv.es, November 7th, 2010.
 Gorenflo L.J., Romaine S., Mittermeier R.A. & Walker-Painemilla K. (2012). Co-occurrence of linguistic and biological diversity in biodiversity hotspots and high biodiversity wilderness areas. PNAS [doi]
 Endangered Languages, A project by the Alliance for Linguistic Diversity, www.endangeredlanguages.com