Deep inside the corpse flower are its developing fruits (painted in the sketch above). After 6-9 months, they’ll look like a column full of beautiful ripe tomatoes, tempting birds to eat them and distribute the seeds inside.
Unfortunately, both the corpse flower (Amorphophalus titanium) and its major seed distributor, the rhinoceros hornbill, are threatened by deforestation. Populations of the rhinoceros hornbill bird (Buceros rhinoceros) have declined by 72%. Other species, such as the orangutan and Sumatran tiger, are also suffering from this habitat loss.
What’s driving the deforestation? Many old growth forests in Sumatra have been cut to make way for palm oil plantations. Are the Sumatrans really eating that much palm oil? Nope. It’s you and me. So check your food labels – sometimes palm oil is listed under “vegetable oil” (if so, it must describe which plants). Look up eateries and food brands by using the Union of Concerned Scientists’ Palm Oil Scorecard – thankfully, Ben & Jerry’s has a good score!
Many flowers use insects to transfer pollen from one plant to another. Some flowers attract bees or butterflies. The corpse flower, though, uses carrion beetles and flesh flies. What attracts these pollinators? The color of decaying flesh, putrid scents, and the warm temperature of a freshly dead body. Lovely.
While we humans tend to focus on color, beetles and flies who pollinate the corpse flower may be more attracted to the scent and temperature. Angioy et al. (2004) showed that certain insects have the abilities to “see” temperatures and are attracted to heat. The heat generated by the spadix of the flower is unusual in the plant kingdom. Not many plants expend tons of energy to warm up to around 100 degrees Fahrenheit. Those few that do are called “thermogenic plants.” It’s generally accepted that the heat increases the range of the odors (Barthlott et al. 2009), which is true of course. But wouldn’t all plants benefit by increasing scent ranges? Yet this mechanism is found in plants that only mimic carcasses to attract pollinators – plants like the skunk cabbage and voodoo lily.
While most flowers give their pollinators a reward of some kind (think nectar), the corpse flower seems to just take, take, take. The plant mimics carrion, where pollinators normally lay their eggs, yet gives the pollinators no food or reward. Or could it?
I personally found it interesting that the spathe of the corpse flower closed back up after it bloomed. It’s probably protecting the developing fruit. Yet the fruit takes 6-9 months to mature. At the Chicago Botanic Garden, the spathe of their corpse flower wilted after about 3 months, exposing yet unripe fruit. Could the flower serve as protection for the developing carrion beetles? Is there any food supply for those youngsters when they hatch? Or is it just a dead end (pun intended)?
FYI: while other arums smell like corpses too (my personal favorite is the “pig-butt arum”), some species of Amorphophallus smell like bananas or carrots.
Angioy AM et al. 2004. Function of the heater: the dead horse arum revisited. Proceedings of the Royal Society Biological Sciences. 271(3) S13-15.
Barthlott W et al. 2009. A torch in the rain forest: thermogenesis of the Titan arum (Amorphophallus titanium). Plant Biology 11. 499-505.