Today, in Mexico and parts of Central America there are still producers called chicleros, who harvest the white sap from the tree trunk, cook it down, and mold it into large bricks of natural gum.

Research has shown, for example, that some individual yellow gum trees regulate their water use ... a lignotuber (a swelling at the base of the trunk containing dormant buds and carbohydrate).

In the ten-minute drive from my house to the Queensland Art Gallery and Gallery of Modern Art (QAGOMA), my taxi passes just ...