Final answer:
Linguistic anthropologists do study deaf communities, which have complete and recognized languages like American Sign Language (ASL). Deaf communities are significant in understanding cultural and social practices through their languages.
Step-by-step explanation:
False. Linguistic anthropologists indeed study deaf communities. Contrary to the assertion in the question, deaf communities do have rich languages. For example, in the United States, deaf individuals often communicate using American Sign Language (ASL), which is a complete and complex language with its own grammar and syntax, used by communities with shared cultural experiences. ASL and other sign languages around the world are recognized for their uniqueness and linguistic value. Linguistic anthropology recognizes and studies these languages because they are central to understanding the cultural, social, and communicative practices of deaf communities.