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LOOKHEAD

The evolution of Specworld plants, while broadly that of our home timeline, has produced species that are, on the whole, nastier than their Home-Earth counterparts, sporting an ingenious variety of spines, poisons, and other deterrents to herbivores. Most botanists agree that the reason for this puzzling phenomenon is that fact that Specworld plant groups never experienced the ‘break’ that Home-Earth’s plants enjoyed in the early Cenozoic, before large, herbivorous mammals had evolved. Spec’s dinosaurs, on the other hand, never stopped munching and stomping on plants, and are generally more efficient herbivores than similar-sized mammals, in any case, so Spec’s flora has had to evolve potent defense mechanisms.

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Paintree (or nettle tree), Urticarbos infernalis (Southeast Asia)

A case in point is the paintree, also known as the stinging nettle tree, or the goddamnbush, a primitive angiosperm that grows in the jungles of southeast Asia, from Burma to Sumatra. These small trees, never larger than four meters tall, are nonetheless immune from the browsing of that area many herbivores. The mighty balundars of the south and southeast Asian forests, giant cenoceratopsians that plow through forests like ambulatory pulp mills, give the trees of pain a very wide berth, and in fact, these unassuming plants are often found in the centers of a tangled mass of shrubbery, miraculously undamaged in the midst of balundaur-wreaked havoc.

The secret to the paintree’s immunity from herbivores is neither subtle nor particularly surprising. The paintree is ridiculously poisonous. Other plants, both on Spec and Home-Earth, deter herbivores with poisons, but the paintree puts them all to shame. This plant is a magnificent chemist, producing a cocktail of toxins that can incapacitate anything with a nervous system. Early researchers believed the paintree relied, like the Anacardiacean cashews, mangos, and poison ivies of Home-Earth, on alkenylphenols to deter browsers. A chemical family that includes the urushi (laquer) produced by poison ivy, alkenylphenols disrupt the hormone pathways in exposed flesh, ‘sensitizing’ whatever tissue they touch. Some humans and animals are profoundly allergic to these compounds, and such toxins are used widely by many Speworld plants. The paintree, however, does not produce such irritants, which is why all alkenylphenol-based treatments for its stings have proved ineffective. The paintree’s principal weapon is, in fact, not a vegetable chemical at all, but a venom associated most often with snakes.

Certain snakes of Home-Earth dispatch their prey with neurotoxins, chemicals that bind to the transmission sites of nerve endings, and either block or redirect the electric signals that they produce. The paintree, along with a few related Spec-endemic species, produces urticarbotoxin, a form of neurotoxin chemically similar to curare and the erabutoxin b used by sea snakes to dispatch prey. These chemicals specifically target the acetylcholine receptors that communicate motor commands from the brain to the body’s muscles. Blocking these receptors, the venom causes violent muscle spasms, leading (if the dose is great enough) to death as the heart and diaphragm cease to function. Along with this potent compound, paintrees also produce a range of neurotoxins aimed at disrupting their victim’s sensory nerve signals, causing loss of vision, hearing, hallucination, and intense pain.

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The leaf of Urticarbos infernalis. The Sumatran subspecies has a differently colored leaf.

The leaves of a paintree are covered in tiny spines, each a tiny hollow silicate cone, which function as tiny hypodermic syringes. The spines ensure that the poisons are injected into the bloodstream of any passing animal, where they quickly bind to nearby nerve endings and begin their terrible work. Small mammals and birds often die within minutes of contact with a paintree’s leaves, and large animals such as balundaurs are beset by grand-mal-like fits and loss of motor function after brushing against one of these trees. With their great size and thick skin to protect them, balundaurs rarely die after external contact with a paintree’s leaves, but they are physically incapacitated for hours, and may fall prey to any number of predators. In the case of humans, brushes with paintrees are often fatal.

The reason for such extreme over-adaptation on the part of the paintree has been the cause of much debate among Spec-botanists in the years since the trees’ discovery. Many other plants, both in Spec and RL make use of a variety of irritants to avoid overgrazing, but very few seek to actively kill their victims, as do the paintrees. The manufacture of urorticarbotoxin is metabolically expensive, and the trees might easily produce some less potent substance and concentrate more effort upon growth and reproduction. The most likely reason for the paintrees’ seemingly ridiculous chemical arsenal is that, while most herbivores can be driven off with a foul taste or a skin irritant, the cenoceratopsians that are the principal herbivores of South and Southeast Asia are not so easily deterred. A balundaur is a plant-eating machine, with a powerful beak and wood-grinding battery of teeth, a crop filled with gravel for further pulverization, and a massive digestion system laden with symbiotic bacteria, that can break down even the least pleasant vegetable compounds. In any case, even if foul taste did prevent a balundaur from eating a plant, nothing short of immediate paralysis on contact would prevent these behemoths from crushing a small tree beneath their enormous bulk. The paintree has taken just such a course, and ensures its own survival by being so incredibly poisonous, that balundaurs and other large herbivores do not even approach.

The paintree’s poison, lethal as it is, is not a panacea, however. Since the paintrees first evolved (genetic evidence suggest they split from basal angiosperms such as magnolias or zlaktopalms during the Eocene), several species of organism have adapted to living with and exploiting these lethal trees. Many other plants, of course, find paintrees very useful, and some have developed reproductive strategies to make sure that they are paired with these venomous guardians. Most of these plants make use of one or another of the paintrees’ animal symbiotes (see below), but one species, the sniffing liana (Olerevitis reperis) seems to actually be able to smell a paintree’s emissions, homing in on the nearest representative from wherever the vine seeds happen to germinate.

Some insects have also adapted to the paintrees. Several species of ant, for example, are exclusive residents of paintrees, physically avoiding the hypodermic spines (in one case) harvesting the poison for their own use.

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Nettletree butterflies; Infernafilius cambodiensis (right), I. formosus (left) (Southeast Asia, Sumatra)

Nettletree butterflies are immune to the trees’ poisons (by a metabolic process still under research), and are their hosts’ principal pollinators. These butterflies are not, themselves poisonous, but rather evade predators by perching on paintree branches and mimicking the leaves. Pictured here are the mainland nettle tree butterfly (right) and the Sumatran subspecies (left), both are colored in accordance with their preferred species of paintree.

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King in yellow, Regipapilio hastur (Southeast Asia)

The king in yellow ( Regipapilio hastur) is another butterfly species immune to the numerous toxins of the nettle tree. However, this species takes advantage of its immunity in a way the nettletree butterfly does not. The king in yellow’s larvae feed exclusively on the leaves of the paintree and stores and the toxins it ingests its own body. King in yellow larvae are thus highly poisonous, themselves, and retain this toxicity into adulthood. The king in yellow is one of the most beautiful butterflies in the southeast Asian jungle, but any animal dimwitted enough to eat one is in dire conditions, indeed. The butterfly’s poison, somewhat diluted from its lethal dosage, is still enough to temporarily blind a large animal. The secretions of the larvae are also said to have hallucinogenic properties, although this fact has yet to be confirmed.

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Cenobite seedcracker, Nucirepertor cenobitoides (Southeast Asia)

Of all the animals to co-evolved with the paintree, the largest, and perhaps the strangest, is the cenobite seedcracker. These little oviraptorosaurs are unusual in that they are the only animals larger than insects able to approach the paintree. In fact, the cenobites nest on paintree roots, which grow in natural “cups” to facilitate the process. The paintrees also tend to grow their draping branches in such a way as to leave clear one or two cenobite-sized paths into the tree’s interior. Cenobite seedcrackers depend upon these paths, because, unlike the insects, the oviraptors’ immunity to paintree toxins is not perfect.

Cenobites are actually quite resistant to paintree excretions---their lymph glands produce an enzyme that binds to the urticarbotoxins and renders them harmless---but this system is fallible. Cenobite lymph glands cannot produce infinite amounts of the anti-venom, and in a body as large as an adult seedcracker, there is still ample chance for a dehabilitating dose. Cenobites supplement their natural resistance by being very cautious around their host plants, sticking to clear paths to get in and out of the tree’s interior, and physically avoiding the leaves. These little dinosaurs are also covered with a thick coat of oily plumage, which shields them against much the tree’s secretions. Over time, however, cenobites are stung so often that the nerve endings around their faces and hands are deadened, making these parts of their bodies almost immune to pain. As a side note, this immunity makes seedcrackers one of the few animals able to eat and spread the seeds of tree urchins, the spiny fruit produced by another of the jungle's plants, bringing yet another species into the paintree symbiosis-net.

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A cenobite lives up to its name. The deadened nerves around this seedcracker's face allow it to chomp a ripe tree urchin.

The deadened nerves around this seedcracker's face allow it to chomp a ripe tree urchin. The otherwise antagonistic paintree’s unusually accommodating nature in the case of the seedcracker has always been something of a mystery, but probably stems from the tree’s overspecialization as a poison-maker and the problems such adaptation can cause an organism. Paintrees are invariably surrounded by dense thickets of undergrowth, as other plants take advantage of the shield from grazing that the tree provides and if allowed to grow unchecked, these plants would soon choke out their guardian. Cenobite seedcrackers, however, forestall this fate by regularly weeding their trees. The little oviraptors have often been observed circling their trees (conscientiously avoiding the leaves), digging up small trees and vines with their powerfully clawed hands. Although the seedcrackers do sometimes eat the plants they excavate, more often they simply uproot the weeds and leave them, demonstrating that food gathering is not the primary purpose of this activity.

Another instance in which the tree’s over-aggression causes it trouble is in reproduction. The fruits of the paintree, like its flowers, are tainted with urticarbotoxins, and, while not actually lethal, are certainly capable of knocking out a middle-sized animal. This toxicity is something of a misfortune for the paintree, as it relies upon animal couriers to spread its seeds. Once again, the cenobite seedcracker comes to its host’s rescue, however. Paintrees produce fruit during cenobite nesting time, at which point they fall to the ground and are gobbled up by the hungry seedcrackers. Much of this fruit paste is stored in the cenobites’ crops, where lymphatic secretions render it relatively harmless. The parents then regurgitate the remains of the fruit (as well as anything else they might have eaten) into the mouths of their chicks. Cenobites thus begin life by ingesting a great deal of low-grade paintree poison, helping their systems to build up an immunity to their deadly hosts before they must venture beyond the nest. In addition, parent cenobites, like many birds and small dinosaurs, is a conscientious nest-cleaner, physically picking up the feces of their young and dumping them beyond the paintree’s curtain. The paintree’s seeds, which passed from the parent to the chick and through the chicks’ digestive system, may now take root and grow beyond the shadow of their parent.

The benefits of the paintree as a host to the cenobite seedcrackers are obvious. Small and unimposing, the cenobites rely on the paintree for protection from predators, raising their young behind curtains of lethal foliage. The paintrees also provide their wards with food, as the killed or stunned of the birds and bats unfortunate enough to brush against its leaves form the bulk of a seedcracker’s protein intake, in addition to paintree fruits and the edible plants that grow around them.

The paintree is a nexus of biological activity, a miniature ecosystem within the larger context of the jungle. These dangerous trees are, however, as much supported by their symbiotes as they are by the trees. Without the attentions of the nettletree and king in yellow butterflies, the paintrees’ flowers would never be pollinated, while the attentions of the cenobite seedcrackers ensure that the trees' roots are free of weeds and that their seeds are spread. This intense co-dependence most likely allowed paintrees to evolve such extreme toxicity. In all probability, paintrees first evolved as only mildly poisonous shrubs, while the ancestors of the cenobites seedcrackers were generalist scavengers, which fed upon the proto-paintrees’ fruits and plants gleaned from the forest floor. As the trees became more poisonous, the seedcrackers would have stayed near the plants for protection, the two species becoming further entwined, their symbiosis allowing each to specialize further, necessitating even greater dependence. The modern species, each the slave of the other, is the result.

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