Natural rubber at least showed promise as rubber sources, include the rubber fig ("Ficus elastica"), Panama rubber tree ("Castilla elastica"), various spurges ("Euphorbia" spp.), lettuce ("Lactuca" species), the related "Scorzonera tau-saghyz", various "Taraxacum" species, including common dandelion ("Taraxacum officinale") and Russian dandelion ("Taraxacum kok-saghyz"), and perhaps most importantly for its hypoallergenic properties, guayule ("Parthenium argentatum"). The term gum rubber is sometimes applied to the tree-obtained version of natural rubber in order to distinguish it from the synthetic version. The first use of rubber was by the indigenous cultures of Mesoamerica. The earliest archeological evidence of the use of natural latex from the
Ficus virens Ficus virens Ficus virens is a plant of the genus "Ficus" found in India, southeast Asia, through Malaysia and into Northern Australia. Its common name is white fig; it is locally known as pilkhan and in the Kunwinjku language it is called an-borndi. Like many figs, its fruits are edible. One of the most famous specimens of this tree is the Curtain Fig Tree of the Atherton Tableland, near Cairns, a popular tourist attraction. "Ficus virens" var. "sublanceolata" occurs the subtropical rainforest of northeastern New South Wales, and south eastern Queensland in Australia. It is a medium-sized tree which grows