It heats up through a process called "thermogenesis" which is
triggered by acetosalycitic acid. It may generate so much heat as to be
30° above air temperature and its purpose, so far as is known, is to
generate volatile compounds which in turn attract insects. In most
genera, including the Monstera you saw, this happens at dusk at which
time the large scarab beetle pollinators are actively flying. These
beetles visit the inflorescences of aroids to aggregate, have sex and eat
edible but unessential parts of the inflorescence (in the case of
Philodendron this is the sterile male flowers which contain nutrient-rich
lipids. The heat peak is timed precisely for this activity and may occur
on the following evening as well when the stamens are opening and they
are leaving, getting themselves covered with pollen in the process of
their departure. For the beetles it is just one long orgy!
On 22 May 00, at 11:47, Chris Tyrell wrote:
Date sent: Mon, 22 May 2000 11:47:00 -0800
From: Chris Tyrell <email@example.com>
Copies to: Dwight Koss <firstname.lastname@example.org>
Hello Mr. Croat,
I got your name from the staff of the LA County Arboretum to whom I had
posed a question. I am not a knowledgeable plant person, I am a lay admirer
of the floral world, that's all. I love to go to gardens.
While in LA, behind a friend's hotel, I saw a huge split-leaf philadendron
(monstrosa?) which had numerous "pods" with points at the top of a growing
shoot. Our of one protruded a long, white, smooth and fleshy thing - a huge
vcersion of that thing that sticks out of antheriums (?). Happily, I was
motivated to touch it, and to my amazement it was HOT!!!
The staff at the arboretum told me I might be able to find out from you how
that plant produces the heat and why. Is there something a lay person could
read about heat production in arcacaea?