Thanks for the book link, I'll certainly look it up if I can find it . : ) It seems to me that the plant takes a lot of effort (which I'm guessing could be better spent doing something else?) for it to shift the spadix over 8 hours into a position before it starts to heat up & become smelly in the evening. The time & energy invested doing that must be for a good reason otherwise I'd imagine that investment would be better spent doing something else & I'd guess it would eventually be bred out through natural selection etc., ? There must be lots of insects who will be attracted by infra red especially early evening when the ambient light is failing. That spathe must look especially brilliant then. I'm guessing anything which can see infra red is going to be attracted in the dark of the evening. Perhaps like moths around a lightbulb etc., do you think? On pollination, I had a good go myself with a small paint brush. At the time I was fiddling around, I noticed there was a little spider which also seemed to be taking an interest around that area. Probably coincidence, but what would prevent that spider shifting some pollen around too? Either way, while its flowering it's been providing me with fascination & speculation with a lovely peppery musk scent too! : )
Heat & the emission of infra red are inextricably linked if I recall my physics correctly. Many thanks for the offer of the texts, I'll look forward to receiving those. I've not had much joy finding the book you mentioned although I'm still looking. < edit: found it - http://www.amazon.co.uk/Aroids-Plants-Arum-Family-If/dp/0881924857 - and duly ordered! > Oh wow! Idly Googling just now I typed in the search phrase 'infra red philodendron' and I found this very interesting link here: http://www.news.wisc.edu/titanarum/facts.html Towards the end of the article there's a couple of really nice images showing a spadix nicely lit up. Stands out against the background?
Ok, I should step in here as a physics geek. Infrared light and Infrared heat are the same concept; all heat is energy produced at the below-visible end of the spectrum of wavelengths available to the human eye. (Although not necessarily to the insect eye.) IR light is the "visible" manifestation of heat - and all metabolic heat, as defined by physics, occurs within the IR spectrum, regardless of what organism is producing it. This is the principle behind some forms of night-vision goggles and certainly behind the IR cameras used by law enforcement to track criminals in the forest.... I'd say that what Chris is after is that the bloom is producing the IR wavelengths during the anthesis, not that the IR wavelengths are the cause of the anthesis.
Hi Steve, Is it me, or has the site been down since Sunday (currently Tuesday evening here) ? What a truly wonderful & very interesting set of replies! How exciting!! Many thanks to you Steve, for your kind help & considerable effort in emailing your colleagues and also their considered & detailed replies. Both spathes which 'flowered' have now completely shut on my Philodendron. But there are another four albeit considerably smaller, in size. I shall try and procure some infra red camera film and have a think of how best the plant could be photographed / filmed. The equipment used to produce the photographs in the link sounds somewhat specialised - I imagine because it will be very sensitive and so may prove tricky to procure. However.... I have a few interesting avenues which have been suggested to me (regarding equipment) I'd like to explore and I shall let you know what happens! One question, the specific beetle pollinator, is it able to fly? <Edit> sorry we cross posted, I am just now reading your second (continued) post with great interest and shall follow up on the links you kindly mention. I shall let you know anything I find/come across immediately! I must confess to feeling somewhat dazed at this very moment. All very exciting! : )
And yes, the site was down - cause unknown yet, but it is running stably right now (or not, it seems - still a bit flaky).
this is a FASCINATING discussion!! i'm learning a great deal about flower pollination - and not just for philodendrons...all this info applies (in a general way) to other species as well! absolutely fascinating! steve, you really are a wonderful writer! i completely understand everything - even though it's pretty technical. you know what? you're about as much of an expert as any person can be barring having a degree in this stuff! as for taking pics, i don't know how long you've been out of the business, steve... wouldn't a digital slr be able to pick up on the infrared light? i'd think so...if some of the pics i've taken with mine are any indication. i haven't had it that long and i've not fiddled with settings yet - i keep getting pics of certain shades that don't show true. i'm sure there's some adjustment i can make (iow, i need to stop using the auto settings, lol) to compensate. so, i'm sure that these d-slr's would be more than capable of being set to pick up the infrared being emitted by the plants.
Some digital SLRs can pick up on infrared light to varying degrees, but they will often need a glass filter in front of whatever lens to exclude other sources of light so as to capture an IR image. Other digital SLRs have such strong infrared-prevention filters above the sensor (including Canons) that even with a glass filter that excludes other wavelengths, it still won't be able to capture IR. I converted an older digital SLR of mine to remove that IR-excluding filter above the sensor with a visible-light-excluding filter, so it can now only be used for IR, at LifePixel.
Here's the correction on the physics end that I was trying to make when the servers died.... All energy is manifested by forms of radiation; what we call the visible spectrum is a fairly small slice of this. Radiation at the Infrared (IR) level is what we term "heat" and also "IR light" - recognising that the eyes of humans are in many cases more limited than those of other species, especially insects. To a species with the ability to see into the IR end of the spectrum, the inflorescence would be lit up like a beacon during anthesis - heat seems to me to be the direct result and certainly part of the point of thermogenesis. (And of course, thermo genesis = "heat birth") Now I'm just speculating, but normally an increase in heat will make smells more intense, so perhaps part of the point of thermogenesis during anthesis is to spread the pheremone that's released even further afield - attracting more pollinators (in this case, the beetles) from a larger area surrounding the plant. Then the IR feature of the inflorescence becomes like a landing beacon. This is especially interesting because at night the regular spectrum is less available to the beetles' eyes, so the inflorescence should literally glow in the dark for them.
Crikey - I've been trying to reply all evening and each time the forum is down? Grrr : ( Then, when I finally come back, there's a whole load of new posts to which I can't reply to as the forum is down again. If this gets posted you guys are going a bit off track as in "my theory" the physics of the matter are quite simple.. : ) The plant is an infra red tart. In order to survive it;s got to smell good... and look good...
I also find this discussion fascinating!! I like Beth's comment about the police chopper chasing someone hiding in the forest, that the IR camera can flush out, similar to motel neon light mentioned by Steve. It just goes to show that collectors/growers observations, although not being entirely scientifically correct or stated/tested in a scientific manner, do have some merit to botanists. I mean this with no malice when I say, sometimes it may help them think "outside the square" Ed
