Hello Paul, I am a descendant of the Dunkley family of Jamaica, W.I. in the Caribbean.
The only information we have is that there were three Scottish brothers, from Glasgow, Scotland. One was a ship's captain in the 1750's and engaged in the slave trade between W. Africa and the States, calling at Jamaica." It was reported that the ship sank off the Jamaican coast and the Dunkley family was left stranded in Jamaica where they later settled.