The most highly developed indigenous life on Poseidous lives in the oceans rather than on land. Land life, limited primarily to plants, appears quite simple in comparison with Earth’s.
Though larger plants have developed vascular systems, similar to Earthly tracheophytes, none have achieved the level of complexity of Earth’s angiosperms (flowering plants). Most land species bear superficial resemblance to Earthly ferns. Some of these grow to impressive heights and offer excellent shade. Photosynthetic plants employ green chlorophyll, giving the landscape the same green appearance that it has on Earth. Since Poseidous has no seasons, virtually all species remain green throughout the year.
Plant classes vary considerably from island to island indicating that parallel evolution has taken place. Some species are common to more than one island. These reproduce by microspores so small that they can remain suspended in the air for months. Scientists theorize that storms and tradewinds have carried these microspores between the islands. Poseidous’s early pioneers introduced numerous flowering plants on several islands. Most of these consisted of food crops from basic grains like rice and wheat to fruit trees, including oranges, apples, dates, and coconuts.
Pioneers planted decorative tropical flowers as well, and in many areas these Earth species have become wild and have started to crowd out native vegetation. Biologists speculate that if measures are not taken to contain imported species, virtually all of Poseidous’s native land plants will become extinct within a few thousand years, superseded by the more efficient alien species from Earth.
Few animal species above the microscopic level live-on land. The few that do are cold-blooded creatures resembling Earth’s amphibians and small, four-legged creatures of the class “inquadra,” similar in structure to Earth’s insects. The number of inquad species in no way compares with the vast number of insect species on Earth. A genus of three-legged amphibians called “ginko lizards” comprises the most unusual of Poseidous’s land life forms. Like most advanced animals on the planet, these creatures exhibit a planar symmetry. They possess two forelegs but only one hind leg resembling a tail. They have one head, two eyes, and one nostril centered on top of their heads. Ginkos scurry about quite nimbly and appear to suffer no disadvantages from their unorthodox design. Scientists believe these tiny animals evolved relatively recently from the fishlike animals of Poseidous’s seas.
No flying species can be found on land save the inquads. Pioneers have considered importing bird species from Earth, but fear the adverse effects these animals might have on vegetation and the local inquad populations.
The richest diversity of life is found in the seas of Poseidous. Only a fraction of the sea species believed to exist have been identified and classified, and biologists estimate there may be half again as many marine species on Poseidous as on Earth. Even a brief description of each class of sea life would run to hundreds of frames.
Many superficial similarities between the sea life of Poseidous and that of Earth appear to the casual observer. Seaweed grows in many varieties from short grasses to tall, floating structures resembling Earth’s kelp forests. Unlike Earthly seaweed, however, many of Poseidous’s species reproduce bisexually, employing multi-colored “flowers” to attract small swimming animals that carry genetic information from one plant to another. Unlike Earth’s flowers, however, these marine plants do not form the rugged seeds characteristic of Earthly angiosperms.
Among the animals can be found all manner of shellfish and arthropod-like creatures with exterior skeletons resembling Earth’s crabs and lobsters. Filter feeders, like limpets and sponges, multi-tentacled animals like squid and octopus, and giant jellyfish all number among Poseidous’s sea life. The most advanced forms are swimming animals resembling Earth’s fish. These range in size from tiny fingerlings to enormous predators that dwarf Earth’s great white sharks. Since they pose considerable hazard to swimmers, Poseidons have ringed their beaches and swimming areas with ultrasonic fields to keep them out.
None of Poseidous’s sea animals have achieved the sophistication of Earth’s great sea mammals, but some animals are more complex and intelligent than Earth’s fishes. The class of “osteicalors” or variable temperature fishes comes in a wide variety of forms. All species swim, but some can fly and others can climb out of the sea onto the rocks of the surf zone in search of food. In shape, most osteicalors have the streamlined form of Earth’s fish, but their tails are horizontal rather than vertical. They use gills to take dissolved oxygen directly from water, but their gills function well enough in air to allow them to remain alive out of water for long periods.
The variable temperature fishes derive their name from their ability to elevate their body temperatures above the level of the surrounding water. They are not truly warm-blooded because their temperatures fluctuate within rather wide ranges depending on the water temperature. Temperature variations of ten degrees have been observed without any apparent adverse effect upon the creatures. Osteicalor species range in size from a few hundred grams to several hundred kilos. Most tend to be vegetarians or filter feeders, though many appear omnivorous. Though some wear brilliant colors – red, blue, and yellow – most blend into the dark greens and grays of the sea. Variable temperature fishes comprise the most intelligent of native life forms on the planet; yet their intelligence in no way approaches that of Earth’s mammals.
Humans can eat some of the marine life on Poseidous, though it took many years of study to increase the range of edible species to what it is today. More than 500 species of edible fish and 250 varieties of edible sea plants have been identified. Many of these are considered delicacies. A great deal had to be learned about the chemistry of Poseidous’s marine life before it could be used as food. As on Earth, many normally harmless sea creatures can ingest microorganisms that turn them from healthful food to deadly poison. Commercial fishers carry real-time analyzers which quickly separate edible species from those containing toxic substances. These devices function so rapidly and precisely that the useless catch can be returned to the sea before it perishes.
The marine life of Poseidous has provided Human beings with more important benefits than food. In the colony’s early years, a form of sea grass found in the tide pools of New Britain caused early pioneers to break out in an all-over body rash when they touched it. Concerned about the potential danger of this plant, medical researchers began to study it closely. They soon found that victims of serious cancers who developed the rash began to exhibit complete remissions of their diseases. Prior to that time, treatment of many of these cancers had been only partially successful and very expensive. Scientists later learned that the Human body’s reaction to the effects of the alien plant stimulated the production of the very antigens needed to detect and destroy the cancer. The analysis of this mechanism provided Humankind with the ultimate weapon to combat this once deadly form of disease.