In Sao Tome and Principe (STP), there are approximately five thousand deaf and hard-of-hearing individuals. Until recently, these people had no language to use between them other than basic home signs used only to communicate with their families. With this communication gap in mind, a project was set up to help them come together in a common space in order to create a dedicated environment for a common sign language to emerge. In less than two years, the first cohort began to sign and to develop a newly emerging sign language -the Sao Tome and Principe Sign Language (LGSTP). Signs were elicited by means of drawings and pictures and recorded from the beginning of the project. The emergent structures of signs in this new language were compared with those reported for other emergent sign languages such as the Al-Sayyid Bedouin Sign Language (ABSL) and the Lengua de Señas de Nicarágua (NSL), and several similarities were found at the first stage. In this preliminary study on the emergence of LGSTP, it was observed that, in its first stage, signs are mostly iconic and exhibit a greater involvement of the articulators and a larger signing space when compared with subsequent stages of LGSTP emergence and with other sign languages. Although holistic signs are the prevalent structure, compounding seems to be emerging. At this stage of emergence, OSV seems to be the predominant syntactic structure of LGSTP, and yet the data suggest that new signers exhibit difficulties in syntactic constructions with two arguments.

In this study, we aim to disentangle pantomime from early signs in a newly-born sign language: Sao Tome and Principe Sign Language. Our results show that within 2 years of their first contact with one another, a community of 100 participants interacting everyday was able to build a shared language. The growth of linguistic systematicity, which included a decrease in use of pantomime, reduction of the amplitude of signs and an increase in articulation economy, showcases a learning, and social interaction process that constitutes a continuum and not a cut-off system. The human cognitive system is endowed with mechanisms for symbolization that allow the process of arbitrariness to unfold and the expansion of linguistic complexity. Our study helps to clarify the role of pantomime in a new sign language and how this role might be linked with language itself, showing implications for language evolution research.