Well more than 100 distinct sign languages exist worldwide, with each having features that made it possible for researchers to create an evolutionary tree of their lineages.

New research suggests that determining evolutionary trees of organisms by comparing anatomy rather than gene sequences is misleading. The study shows that we often need to overturn centuries of ...

Douglas and senior scientist Peter Wills applied the model to cephalopods (including octopuses, squids, cuttlefish, and vampire squids), as well as to the evolution of Indo-European languages, and ...