The Scientific and Cultural Cost of Convenience Sampling in the Face of Rising Language Endangerment: Highlighting the Role of Language Acquisition.

We live in an unprecedented era of language endangerment and loss. In the midst of this crisis, it is becoming more and more evident that the psychological and cognitive sciences know very little about how most of the world's languages are acquired, represented, and processed. Therefore, the opportunity to understand our most important and defining species-specific trait is being rapidly lost. In this Perspective, we highlight the extent of this problem, focusing on a key group at the heart of language transmission and loss-child language learners. We show that, due to sampling biases, very little is known about how children learn much of the vast corners of the linguistic design space, and that our opportunity to do so this is fast running out. We end by arguing for the greater integration of the academy, government, and community in addressing this problem.