Tamjack

The tamjack split from its ancestor. Their fur has shortened and they have become more streamline in order to swim faster, its movement similar to Earth's otter. The scales on its back have shrunk and increased in number. They now serve the same function as the scales on Earth sharks in that they direct water into currents over the body, thus increasing aerodynamics. Their primary adaptation is their tail. Instead of being a thick rudder, it now has serrated edges like a saw. Not only does this allow individuals to chop down larger flora for use in their floating nests, but the grooves also add power to their swimming strokes, in a similar way to the bumpy grooves on Earth's humpback whales; they can also swing their ax-like tail as a weapon in and out of the water if they are threatened. It has become so successful that it has replaced its ancestor in all but the southern coasts of Dixon.

Because of the new tail, their nest-building technique has changed. They now use the fuzzpalm as the central structure of their nests, chopping down and sectioning off trunks to act as ribs for the structure; this is possible because the fuzzpalm's wood is flexible while alive but stiffens in death, allowing freshly-cut trunk to be bent into permanent shapes. They then use the waterproof properties of the fuzzpalm's berries as well as adhesive compounds in their own saliva to create a sticky paste that binds the trunks together. They then coat the outside and inside with a thick wall of other flora. Their dependance on the fuzzpalm has lead them to carry supplies of fuzzpalm berries to both patch up holes in their nests as well as to plant new groves of fuzzpalms for construction. Because of this, the fuzzpalm has spread to all the beach biomes the tamjack inhabits.

Individuals live for 25 years. A Female gestates young for a half a year and give birth to 2-4 babies 3 times in her life. Like their ancestors, they are warm blooded and give birth to live young. The live young live in the warm pouch until they either have grown too big or they grow scales. However they will still nurse milk from the mother for up to a year after birth even if they cannot fit in the pouch. Females do not leave the floating home since it would drown their babies. Males must bring food back to their home for its mate and offspring. Even after weening the young will stay with their parents for another 4 years, helping to repair and protect the nest. They then live alone on the beaches for about another year or until they stumble upon a potential mate, after which they will mate and build a new nest.