Dikaryotes

Dikaryotes are one of two eukaryote analogues on Ilion. Beginning with a small array of organelles and many copies of an ancient plasmid-containing structure called the paranucleus, dikaryotes developed a two-nucleus system for storing most of their native genetic material. The other group, parakaryotes, evolved a more complex paranucleus.

Phylogeny of Dikaryotes

Naked triflagellates – Lacking the hard skeleton of their sister clade, naked triflagellates are more active in their pursuit of live microbes. Parasitic and pathogenic species rely on animals and plants to complete their life cycle.

Armored triflagellates – The calcium and silicate skeleton of armored triflagellates varies in shape and structure but it is always triradially symmetrical. Together with babel algae and extinct shelled animals, they are responsible for most of the planet’s limestone.

Magic carpets – As a precursor to the plicozoan method of gastrulation (that is, folding into a tube to form a gut), individual cells aggregate into a sheet one to four cells thick. The sheet is capable of basic undulating movement. Its surface contains proteins that catch and digest marine snow as it falls from the ocean’s photic zone. Magic carpets are found in all zones of the lightside oceans but they are most common in the abyssal zone, where few predators lurk.

Protomotilia – This is the plicozoan in its simplest form: a tube of undifferentiated cells. Most are filter feeders, while a few rare species harbor chemosynthetic microbes around hydrothermal vents.

Motilia – Motilia includes all of Ilion’s plants and animals.

It is not uncommon for dikaryotes to receive plasmids from unrelated organisms. Pink algae (allorosea) contain many copies of the photosynthesis plasmid, so it is no surprise that this plasmid would make its way into three different organisms: red algae (eurosea), red plants (within motilia) and dikaryotic algae, which include babel algae, colonial algae, and several minor clades that are not shown. An additional photosynthetic pigment unique to dikaryotic algae gives them a wine-red hue.

Babel algae – The allorosean photosynthesis plasmid is not the only foreign genetic material this group has received. A group of genes that codes for a silicate skeleton crossed over from the armored triflagellates. When combined with native regulatory genes, the skeleton grows spiralwise, giving the cell an appearance that, to some, brings to mind the Tower of Babel.

Colonial algae – Colonial algae grow in colonies one cell thick with dichotomous branching. The filaments of colonial algae can extend quite far but they are fragile. They are common in freshwater lakes and gently flowing rivers.

dikaryotes cycleThe cycle varies from one phylum to the next, with some emphasizing the dikaryotic phase and others living most of their lives in the haploid phase, and still others spending a good deal of time as diploid organisms. Still, all dikaryotes pass through every stage throughout their life cycle.

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