Iguanas speak a foreign language.
They have a limited vocabulary, one that, like some spoken languages, has some very subtle nuances in pronunciation. They are easily able to communicate with other iguanas in this language of the body. It is up to us to learn to at least read their language, interpret their postures, movements and placements, and to learn how such movements on our part may communicate action or intent, intentional or not, on our part. When the dewlap is fully tucked up under the chin, the iguana is signaling submission. Baby iguanas are often thought by their owners to not have dewlaps, as the owners never see them for the first several weeks.