Ficus tinctoria dispersed by people?

Ficus tinctoria grows throughout the pacific islands and has many uses. The fruit is a staple food for some cultures and can be crushed to produce a dye, hence the common name of ‘Dye Fig’. Other parts of the plant are used for to create fiber and medicines. Its growth habit can vary from a small rambling shrub to a tall lofty tree, growing on rocks, as a strangler or directly in soil.

 

Ficus tinctoria growing as a strangler, Emma Gorge, Western Australia.
Ficus tinctoria growing as a strangler, Emma Gorge, Western Australia.

 

The Australian distribution of Ficus tinctoria is a little unusually. There are two small populations. One on the east coast of Queensland, which I had previously written off as being incorrectly identified as Ficus virgata  which I am yet to see them in the wild or the herbarium. And another population in Western Australia. After recently visiting some of the Western Australian population, it struck me how unusually it was for these trees to be growing where they are. Here is a plant that grows through out the pacific islands and so how did it make its way to the middle of arid Western Australia.

One explanation could be that it is a remnant rainforest tree, which may be true, though I think the area was dried out a long time before the arrival of this plant. My thought is, that Ficus tinctoria was relocated by people. The Western Australian location I saw is a perfect place for people to live, a little oasis in an otherwise dry and hot region and with this plant having so many uses it would make sense for people to move it there.

A 2010 study showed that Livistona palms arrived in Australia about 15,000 years ago and plants from Northern Territory made their way 1000 kilometers to another location in Western Australia, probably with human intervention. Another paper used DNA and Aboriginal stories to recreated the distribution of Baobab trees across Australia, finding that “ancient humans significantly influenced the geographic distribution of Adansonia (Baobab) in northwest Australia”. It would be interesting to see if DNA could reveal where the Australian Ficus tinctoria came from. Were they introduced by seafarers? Are the two Australian populations genetically identical or were the two populations established independently by different groups of people? Have the tinctoria and virgata of Queensland interbreed? So many questions!!!

 

Ficus tinctoria foliage and fruit.
Ficus tinctoria foliage and unripe fruit.

 

Ficus tinctoria foliage.
Ficus tinctoria foliage.

 

Human-mediated introduction of Livistona palms into central Australia: conservation and management implications

New Genetic and Linguistic Analyses Show Ancient Human Influence on Baobab Evolution and Distribution in Australia