Okay, so this is like really, really cool. Victoria Gill, writing for BBC, lets us in on the coolness:
In Africa and in the tropics, armies of tiny creatures make the twisting stems of acacia plants their homes.
Aggressive, stinging ants feed on the sugary nectar the plant provides and live in nests protected by its thick bark.
This is the world of “ant guards”.
The acacias might appear overrun by them, but the plants have the ants wrapped around their little stems.
These same plants that provide shelter and produce nourishing nectar to feed the insects also make chemicals that send them into a defensive frenzy, forcing them into retreat.
It is actually a fairly intricate relationship, with the ants territorially protecting a food source, including the swarming of larger herbivores, and the tree being able to chemically prevent the ants from causing too much havoc. Dr. Nigel Raine, at University of London, explained:
“The flowers seem to produce chemicals that are repellent to the ants,” said Dr Raine. “They release these particularly during the time when they’re producing lots of pollen, so the ants are kept off the flowers.”
In recent studies, described in the journal Functional Ecology, Dr Raine and his colleagues found that the plants with the closest relationships with ants – those that provided homes for their miniature guard army – produced the chemicals that were most effective at keeping the ants at bay.
“And that was associated with the flower being open,” he says. “So the chemicals are probably in the pollen” ….
…. The repellent chemicals are specific to the ants. In fact, they attract and repel different groups of insects.
“[The chemicals] don’t repel bees, even though they are quite closely related to ants. And in some cases, the chemicals actually seem to attract the bees,” says Dr Raine.
The researchers think that some of the repellents that acacias produce are chemical “mimics” of signalling pheromones that the ants use to communicate.
“We put flowers into syringes and puffed the scent over the ant to see how they would respond, and they became quite agitated and aggressive” he explained.
“The ants use a pheromone to signal danger; if they’re being attacked by a bird they will release that chemical that will quickly tell the other ants to retreat.”
Dr Raine says this clever evolutionary system shows how the ants and their plants have evolved to protect, control and manipulate each other.
The thing is that there is much more to the life of plants than we generally understand. Over the years, plenty of ideas have suggested an increased regard for flora. When I was young, I had some of those Charlie Brown books of nifty facts about the world, and one of them asserted the existence of an m wave emitted by certain trees when their trunks are cut. True enough, I’ve never found another reference to the phenomenon, but when you grow up in the Pacific Northwest with that kind of notion in your head, the band name “Screaming Trees” makes more sense to you than it should.
There are also those mobile forests of fantastic lore. Wizard of Oz, H.R. Pufnstuf, even the Evil Dead films. I don’t think the idea is particularly unusual. But I did once entertain the notion of writing a story describing how trees—stuck in the ground—might network their intelligence; probably science-fiction instead of fantasy, with the hot botanist and the dreamy sergeant making a desperate last stand atop a lone butte emerging from miles and miles of dense, sentient, angry jungle.
Anyone remember the X-Files episode that, while it didn’t exactly meet such standard, involved a predatory, giant, hallucinogenic mushroom.
Or recall the famous and entertaining argument between Arthur Dent and an extraterrestrial bovine in Adams’ The Restaurant at the End of the Universe:
“That’s absolutely horrible,” exclaimed Arthur, “the most revolting thing I’ve ever heard.”
“What’s the problem Earthman?” said Zaphod, now transferring his attention to the animal’s enormous rump.
“I just don’t want to eat an animal that’s standing here inviting me to,” said Arthur, “it’s heartless.”
“Better than eating an animal that doesn’t want to be eaten,” said Zaphod.
“That’s not the point,” Arthur protested. Then he thought about it for a moment. “Alright,” he said, “maybe it is the point. I don’t care, I’m not going to think about it now. I’ll just … er …”
The Universe raged about him in its death throes.
“I think I’ll just have a green salad,” he muttered.
“May I urge you to consider my liver?” asked the animal, “it must be very rich and tender by now, I’ve been force-feeding myself for months.”
“A green salad,” said Arthur emphatically.
“A green salad?” said the animal, rolling his eyes disapprovingly at Arthur.
“Are you going to tell me,” said Arthur, “that I shouldn’t have green salad?”
“Well,” said the animal, “I know many vegetables that are very clear on that point. Which is why it was eventually decided to cut through the whole tangled problem and breed an animal that actually wanted to be eaten and was capable of saying so clearly and distinctly. And here I am.”
It managed a very slight bow.
“Glass of water please,” said Arthur.
And, of course, I recently posted a story about plant behavior and moral considerations of diet.
Or, to revisit Huxley yet again, and so soon:
The spectacle of a dying animal affects us panfully; we can see its struggles and, sympathetically, feel something of its pain. The unseen agony of a plant leaves us indifferent. To a being with eyes a million times more sensitive than ours, the struggles of a dying plant would be visible and therefore distressing …. The poison flower manifestly writhes before us. The last moments are so distressingly like those of a man, that we are shocked by the very spectacle of them into a hitherto unfelt sympathy.
Sensitive souls, whom a visit to the slaughterhouse has converted to vegetarianism, will be advised, if they do not want to have their menu further reduced, to keep clear of the Bose Institute. After watching the murder of a plant, they will probably want to confine themselves to a strictly mineral diet. But the new self-denial would be as vain as the old.
What are we, eighty-three years later, and that just doesn’t sound so crazy, does it?
Of course, I don’t expect to be eating an acacia tree anytime soon. Nor a bunch of ants; I always hate reading the instructions on the box of toothpicks while trying to get the legs out of my gumline.
But I will be eating a dead bovine soon enough. And there are a couple of variations of dead pig in my refrigerator right now. Maybe I should get one of those Bibb lettuce heads, still on the root, and after I tear it up into a salad—maybe with some diced apple, dry cheese, and honey mustard—maybe get out a microscope and watch the poor thing in the throes of agony.
Food or fiction, take your choice. I’m sure there is something theological, or at least philosophical, to consider in all that, too, so let me know. At any rate, this is the sort of news that is just really, really cool.