Who do langurs drink salt water?

A new study shows the remarkable adaptability of the critically endangered Cat Ba langurs. Despite low genetic diversity, the langurs have retained key genetic traits that help them survive in their isolated environment on Cat Ba Island in Vietnam. One of the remarkable adaptations is the ability to drink salt water. Due to the dramatic decline of its population, the species suffers from genetic impoverishment, high inbreeding and a potentially increased susceptibility to disease. Analysis of their genetic information shows that genetic diversity has been maintained in functionally important areas of their genetic information. This enables the Cat Ba langurs (Trachypithecus poliocephalus) to continue to cope adequately with changing environmental conditions. This extraordinary ability is a direct consequence of their isolated island home, where there are only limited freshwater sources. The researchers show that changes in certain genes have probably increased tolerance to salt water. These genetic adaptations enable langurs to cope with the high sodium content of salt water and thus contribute to their survival in this unique environment.