There are two clusters of Amazonian trumpeter species on the phylogenic tree because the main population of the common ancestral species was divided into two different, isolated populations. This is from them that all the other species evolved.
The trumpeters refer to a family of birds found in humid forests of the Amazon and Guiana Shield in South America. Their name has an interesting reason. It is said that they are named for the trumpeting or cackling threat call of the males