| abstract
| - The symbionts are marching. A temporary and small retreat of the northern icecap has created vast new tundra areas over the northern continents. For the first time in 5,000 years the rate of melting of the edge of the glaciers is exceeding their rate of southward movement. In effect, the edge of the icecap is melting back. Rocky debris, broken up by the weight of the ice and shoved along the ground by the southward movement, now lies in hummocks and thick beds of mixed clay and boulders. Here and there a long winding esker (a steep ridge of rubble marking the old course of a subglacial river) snakes across the plain. Huge lumps of abandoned ice embedded in the clay melt slowly, gradually becoming lakes. Yet below the ice-free surface the soil is still permanently frozen. Little grows here, except for the hardy grasses and reeds along the sides of the lakes, and the mosses, lichens and heathers that form tussocks over the rocky soil. Away to the south lie the great forests, which are already spreading northwards into this newly-exposed land, with their outposts of stunted willows, birches and rowans, backed by the dark palisades of spruce and pine. It will be a short-lived advance if the ice moves south once more. It is the domain of the symbionts. From a distance as they trek across the plain they look like the tundra-dwellers, but they seem to be bigger and rather top-heavy. A closer look shows them each to have what appears to be two heads - a large one surrounded by the woolly ruff of blubber, with small eyes and large nostrils, and beneath the chin a smaller head with big ears and active, darting eyes. The herd consists of about 30 individuals, adult and juvenile. They follow the biggest, whose lower "head" seems to be looking around all the time for the best way to travel. It stops, staring away into the distance. A dark flock of birds circles in the far sky, something that should be investigated. The leader's arm shoots out in that direction (an amazingly slender arm for a creature of such a size) and it turns towards the distant flock. The rest of the herd turn as well, each one also shooting out an arm. After a while they come to the site of the disturbance. Most of the birds are hawks, and every now and again one swoops to the ground and carries away something small and furry. There are small arctic foxes there as well, but these turn and scatter as the symbionts approach. The cause of the activity is now visible before them. A mass of small rodents (lemmings) is on the move. Every now and again, in times of relative plenty, they breed prodigiously, until there are so many that the food in their area runs out. Then they move en masse to find new foraging regions. The symbionts have just come upon one such migration, a moving furry layer that stretches in a straight line along the ground towards a possible distant food source. If the movement of the rodents is remarkable, what then happens to the symbionts is even more strange: about half of the individuals fall apart, literally. Each one resolves itself into two separate creatures. The huge hairy arms of the carriers that were clutched across its chest open up like doors, and to the ground drops a spindly figure - the owner of the "second head" and the pointing arm. The slimly-built creatures are running as soon as they hit the ground, and ten of them plunge into the moving mass of lemmings, snatching and killing as they go. The remaining symbionts, mostly females and young, stand watching, shouting encouragement in words and noises that only members of their own group can understand. The symbiont carrier shapes vacated by the hunter symbionts stand immobile and silent. After a while the hunter symbionts gather up the rodents that they have killed and bring them back to the group. They are handed around to the figures clutched to the bosoms of the carriers. Then each hunter symbiont returns to its own carrier and, with a touch and a word, it is gathered up into the great arms. For a while they eat. Each lemming is partly eaten by the being at the symbiont carrier's chest, but then the greater part of it is handed up to the great mouth in the head above. The carrier part of the creature receives the food passively, and eats it all. This strange state of affairs began thousands of years ago. When the temperate woodland-dwellers (the humans that had been engineered to live in the temperate forests) spread out to hunt on the tundra, with the coming of the current ice age they had to adopt all kinds of strategies to keep themselves warm and to survive. Some found that they could live close to the dull tundra-dwellers and share their body heat. The tundra-dwellers did not mind this, if the temperate woodland-dwellers shared their food with them. So the symbiotic situation gradually developed, until now the newly-evolved hunter symbionts could not travel by themselves in the tundra and these particular tundra-dweller descendants (the symbiont carriers) would not be able to survive on their own. Once the food is eaten, the group sets off again. The smaller hunter symbionts can talk to one another, using a simple language, but each communicates with its carrier by nudges and gestures - a pointing of the arm is enough to tell the carrier to go, and which way. They follow the lemming march, as there will be good eating here for a day or two.
|
![[RDF Data]](/fct/images/sw-rdf-blue.png)