Making a Hash of It
Scientific inspiration can strike at any time and in any place. Who knows what Apollyon was up to when this thought struck...
What benefit does THC1, the chemical that makes marijuana fun, provide for the cannabis plant?
As seems to be the way of the SExperts, there were three competing theories. But which two would be weeded out as dopes?
1. Spreading Seeds
Ste's hypothesis, which he confessed was speculative, was that it was a way of encouraging animals to consume the plant and spread the seeds, particularly as THC is produced in the highest concentrations by mature female plants. Alternatively, THC could act as an insect attractant, ensuring that pollen is spread.
The idea of THC as an attractant was, however, soundly refuted by Traveller in Time:
As far as I can find out the production of THC is peaking in female plants without fertilisation. This makes it less likely for the plants to attract large animals to spread their seed.
The cannabis plants use wind pollination, so attracting insects is also less likely.
2. Reflecting Rays
If not an attractant, perhaps THC has a protective function. Orcus suggested that THC may protect cannabis plants from damaging ultraviolet light.
It's well known that in order to get the plants to produce lots and lots of THC, you grow them under powerful UV lamps.
A little more research, however, and Orcus managed to overturn his own hypothesis:
It's not the UV exposure that you use but the fact that you must vary the length of time you expose them to light. It seems the plants flower naturally at the shortening of days and so, by lowering the length of time you light the plants, you fool them into thinking the days are shortening and they begin to flower, which is when they produce the most THC2.
3. Beating Bugs
Having discarded these two theories, we're left with a suggestion from Traveller in Time that THC is an insect repellant. Some insects cause great damage to plants, so plants can produce chemicals that either harm or simply put off such creatures. In support of this theory, Blatherskite the Mugwump produced an interesting paper published in the Journal of the International Hemp Association3 suggesting that THC production is indeed a 'subtle system of insect control by plants'.
And plants aren't the only ones. At the same time he was wondering about THC, Apollyon was also wondering about botox:
Why does Clostridium botulinum produce botulinum toxin? Does it actually do anything for the bacterium?
It seems that botulinum toxin and THC are produced by their respective organisms for similar reasons. As Ste put it:
The toxin kills stuff around the bacteria that is not the bacteria itself. This enables the bacteria to grow and multiply with less competition.
Similar maybe, but perhaps not a good idea for humans to confuse one with the other...