Salpfish1 is the creator of several worlds, including Tregama, home of swimming creatures with siphon-legs and the charybdis fish, which uses suction to create whirlpools and feed on anything on the water’s surface. He also creates a variety of future Earth animals, such as land anomalocarids, fish-like mollusks that eat anemones and then spit stinging cells at predators, and pigs that hunt like frogs. Another favorite of mine is the blind, flying, cave shrimp.
If you are a world builder who needs to ground your life form designs in scientific plausibility, the podcasts at BEKernWrites.com are a good place to start. Each runs about forty minutes long. Subjects such as biomes, metamorphosis, metabolism, and genetic material are covered by an actual professor of biology. The lectures stick pretty close to describing Earth life most of the time while briefly mentioning some of the variations found across the galaxy. It is not wildly speculative.
Nearly all life in the galaxy is descended from the same ancestor through the process of panspermia – and something is trying to kill it. The Sage of Sagittarius by Kenn Brody is a fast read. It is full of scientific details, but without slowing down the action at all. The end is satisfying without being too unrealistic (the “bad guy” is destroyed, but at a heavy cost). Each twist makes sense in the context of the story. The characters are quirky, yet believable, and fairly well developed without getting bogged down in a lot of internal musings – nothing wrong with that, but this book’s focus is on the struggle for survival between species of radically different biology (and physics).
In the course of the story, the characters encounter many alien ecosystems. I liked the mollusk-like beings that sift gold from the sea. I liked the “birds” that planted themselves into the ground and became trees. I liked the centipede-like creatures that kept harems. I loved it.
Concavenator is the creator of Horus, a world connected to Victorian-era Earth via wormhole. It is home to red plants with hearts, tube-jet fish, and large land vertebrates. The animals have a double spine. The dorsal spine runs from the skull along the back, while the ventral spine runs from the chest along the tail. They are connected by ribs. The tail houses the respiratory and sometimes reproductive organs. The land animals have six limbs. Some run on the hind limbs and use the forward limbs for grasping while the middle limbs are vestigial. Others stand on the front limbs while the rear four are used as wings. My favorite is the lazy animal that uses its front limbs to carry its head around while it grazes.
Tapejara is the creator of not one, but six worlds, including Tunjera, Adam, Eve, Lyell-3, Toci-1, and Midgard. They are currently all unfinished but all have huge potential. The animals are very creative. Planet Adam is home to “fish” with large ventral “mouth-bodies” attached only by a narrow tube containing the esophagus. Planet Eve is home to completely armored creatures whose only openings (the mouth and anus) are both located in the head. Some are colonial. Toci-1 is home to animals with chain-link ribcages, helical muscles, and specialized organs capable of regenerating any damaged tissue anywhere in the body – as if all the stem cells were in one place.
Avancna is the creator of planet Tlaquanaru. Although the map proves it is certainly not Earth, the animals are eerily similar to those of our world. There are what appear to be descendants of iguanas, birds, moths, and very many fish. My favorites are the rolling echinoderms and the rotifer-cephalopod-creatures that drop pom-poms full of ammonia to deter predators.
Ramul is the creator of Red Earth, a planet about halfway between Earth and Mars in all its characteristics. It is home to a staggering number of octopod species, but my favorites are the worm grasses (plant-like animals), siltribbons (worms with long mouths that suck up muck), monolingulates (filter-feeding squid-things), and the era worms, which are known to hatch all at once and secrete a poison that kills everything around them.
Biofauna25 is the creator of not one, but two worlds, Epimethius and Odin. Either project has the potential to be a great book.
Epimethius is a larger, stormier version of Earth. There are at least four lineages of plants, including the ridge-leaves, the maze-roots, the feather plants, and the peeling plants. There are an incredible variety of radially-symmetrical animals, some resembling insects, crustaceans, mollusks, amphibians, and mammals. Variations on the theme include laterally flattened shrimp-like forms (making them bilaterally symmetrical) with their eyes on the back end. There are even more bilaterally-symmetrical animals. They have dual ribcages. The ventral ribs house the digestive organs and the dorsal ribs house the heart and respiratory organs. Many resemble fish and snakes. Others resemble deer or crocodiles. Some make silk, some retract their heads into hoods, and others have their simple mouths in the chest. My favorites are probably the frog-like potes.
Odin is a small, relatively dry planet largely covered by inedible sheddings of red plants floating in the air. Different species of floating plants receive energy from sunlight, lightning, or wind motion. They form wide nets to safely diffuse electrical discharges. There are three main groups of animals. The first has a four-stage life cycle, the second has a five-stage life cycle including a sessile phase that feeds the young with nectar, and the third has a five-stage life cycle like the others, but in reverse. I don’t know exactly how he organizes them into groups, but I estimate there must be at least twenty-seven orders.