Nut of note: 70% of world's macadamia can be traced back to single Australian tree

New research shows a single 19th century tree in southern Queensland gave rise to the world's dominant plant variety

The small Queensland town of Gympie has been identified as the origin of 70% of the world's macadamia nuts.

New research into the fatty seed has revealed the world's dominant commercial cultivar - grown in Hawaii - originated from a single tree in southern Queensland from the 19th century.