The Bengal Swamp has become so dangerous, so full of large predators like the lurkfish, that some other creatures have taken refuge out of the water. Indeed, the atmosphere of this hot swamp is so humid that many aquatic animals can spend time on land and not suffer any discomfort.
One creature to have taken advantage of the relative safety of land is the swampus. It is a cephalopod, an octopus specifically, a distant cousin of the marine octopuses that have been so prevalent throughout previous times, dating back to the Late Carboniferous (or Pennsylvanin). The swampus has evolved to survive on land, but for limited periods of time. It is unable to breathe properly out of water and relies on finite stores of oxygen in its tissues and blood. Once these reserves have been depleted, it must re-submerge itself in the swamp water to replenish its oxygen supply.
Swampuses that have used up the reserves of oxygen stored in their tissues and blood gradually become more and more desperate to submerge and breathe properly.
In most respects, the swampus looks like a typical octopus. One difference is immediately apparent: at first glance this creature appears to have four tentacles instead of eight. This is because four of its original tentacles have evolved into weight-bearing pads which it uses to move over land. They function like the foot of a gastropod, carrying the animal along by a rippling action of the muscles. The suckers of the tentacles have developed into horny ridges that grip the ground beneath them. The long tentacles at the front of the swampus are also used in locomotion, reaching out to grip the ground, and then pulling the creature along. It is a clumsy movement, but sufficient to carry the animal's 44-pound (20-kilogram) weight through the thick vegetation of the humid swamp.
The swampus can survive on land for up to four days at a time, safe from the electrical attacks of lurkfish. However, it must return to the water to replenish its oxygen supply and carry out other vital functions, such as mating. The murky water is no place to rear a family, though. Once she has mated, a female swampus clambers out of the water and into the surrounding vegetation to find a safe place in which to deposit her fertilized eggs.
A mother will head for a spray of lilies which serve as a nest in which the eggs can hatch. This nursery plant produces a flush of large, vase-shaped leaves close to the ground. Rainwater partially fills newly unfurled leaves, creating freshwater pools. The leafy pools act as protective cradles for the eggs and young of the swampus.
A pregnant female swampus returns to the same patch of lily plants year after year. She deposits her eggs in the rainwater pool and stands guard over them while they hatch, protecting both flower and brood. Throughout evolutionary history, cephalopods have been unable to cope with freshwater, and the young swampuses are no different. To solve this problem, the mother has evolved a means of changing the chemical composition of the pool. From time to time, she urinates in the water in order to recreate the salty environment of the swamp. Then, by splashing about in the water with her tentacles, she oxygenates it and her offspring are able to breathe. She also brings food to them, such as small ray-finned fish she has caught from the swamp water.
The mother must also breathe and, to do so, she must leave her offspring and return to the swamp. Her young are not abandoned, but left in the charge of other adult females who have deposited their eggs in nearby lilies. They continue to monitor the chemistry and oxygen content of her nursery as well as their own.
On her return, the mother recognizes her babysitter by means of a complex communication system. Her tentacles are se
nsitive to touch and chemical signals, and so she is able to recognize the particular taste and texture of other individuals. This system works well because related females bring up their young at the same time in other lilies of the same patch. Swampuses are highly social creatures.
Like its relatives, the swampus is a master of camouflage. By stimulating chromatophores in its skin, it can change its color to blend in with its surroundings. The knobby surface and serrated edges of its tentacles mean that it can lose itself in the tangle of vegetation and detritus that litters the swamp floor. In this way, it can become almost invisible. Of course, this ability to mimic its surroundings is not just used for self-defense. The swampus is an accomplished predator and uses its flexible, prehensile tentacles to catch large insects and small vertebrates which inhabit the undergrowth of the Bengal Swamp.
The swampus has one more weapon in its considerable arsenal. All octopi have a venomous bite which they use to subdue prey. The swampus employs a similar strategy, and the story of how it obtains the toxins for its noxious weapon is one of remarkable coevolution.
The lily's vase-like basin contains a growth of bacteria. As baby swampus grow up in their organic nursery, they gradually ingest the bacteria. Once ingested, the bacteria form the basis for the swampuses to generate their own venom. Babies and adults use the venom to defend their nursery from large herbivores which feed on the plant. In return for a safe home in which to grow up, the swampuses provide protection for the lily. Any herbivorous animal feeding near the swamp lily is swiftly repelled by a nasty injection of poison that can kill an 8-ton juvenile toraton. However, adult toratons are too big for even a swampus to kill.