Tuesday, May 13, 2014

Ants in your plants--symbiosis in the Wet Tropics

Prickly Ant Plant at Keating Lagoon near Cooktown
Ants in Your Plants! Not in your pants. That's a children's ditty.

Prickly Ant Plants.
Symbiotic or mutual relationships in nature can be very fascinating, but here's one that beats them all.

It's a triple whammy of the natural world and it taking place right now throughout Cape York.
You can find specimens in the  among the mangroves at Cowie Beach, along Marrja Boardwalk at Cape Tribulation, among the melaleaucas at Keating Lagoon outside Cooktown, and the Natures Powerhouse Botanic Gardens at Cooktown.
 By far the most easily spotted is in the gardens outside James Cook Museum, where one endemic  Ant Plant species is nicely plaqued and presented on a paperbark tree.

Ant plant at Marrdja Boardwalk growing among mangroves

The Ant Plant (myrmecodia beccarii) is an epiphytic plant with fibrous inner chambers. It usually grows on paperbarks (melaleucas) or mangrove species. Superficially, it looks like an orchid, but close up, you can see that the outside is covered with prickles.
The real action is inside. Golden ants live inside the chambers and patrol the plant to remove leaf-eating pests. Their excreta is absorbed as food by the plant. That's a genuine symbiotic or mutual relationship.

The next symbiotic layer is the arrival of the Apollo jewel butterfly, the larvae of which live inside the plant. They seem to eat either the ant plant tissue and leaves or ant larvae. The butterfly larvae then provide honeydew as food for the ants. In appreciation, the ants protect the larvae.

Complicated? Incredibly so! Interdependency or mutualism--sometimes co-operative, sometimes not.
Figs need wasps to pollinate each and every fig. Buff-breasted paradise kingfishers bore a hole into and inhabit termites nests.