Founder’s Briefs: An occasional series where Mongabay founder Rhett Ayers Butler shares analysis, perspectives and story summaries. A new report, “Primates in Peril: The World’s 25 Most Endangered Primates,” catalogs the species closest to the brink. Compiled by more than 100 scientists and conservationists, it’s a stark warning: without urgent action, some of our closest relatives may soon be gone. The list spans four continents, taking in the Cross River gorilla (Gorilla gorilla diehli) in West Africa — fewer than 250 individuals remain — to the elusive Tapanuli orangutan (Pongo tapanuliensis) in Sumatra, first described in 2017 and already reduced to just 800 individuals. In Madagascar, home to some of the planet’s rarest biodiversity, the red ruffed lemur (Varecia rubra) and Madame Berthe’s mouse lemur (Microcebus berthae), the smallest primate in the world, are confined to shrinking scraps of forest. In Asia, the primates of the Mentawai Islands in Indonesia, are vanishing under the twin pressures of logging and hunting. In South America, urban expansion and agriculture are pushing the pied tamarin (Saguinus bicolor) and Peruvian yellow-tailed woolly monkey (Lagothrix flavicauda) toward extinction. This is not a new story. Since 2000, the IUCN’s Primate Specialist Group has tracked the most threatened primates. Of the 721 recognized species and subspecies, nearly two-thirds are now endangered. Entire genera are in jeopardy: every species of gibbon, all 17 red colobus monkeys, and 95% of Madagascar’s lemurs. Behind the names and statistics lie familiar culprits: deforestation, illegal trade, climate change. Conservationists have developed detailed…This article was originally published on Mongabay