Multicellularity
The current theory as to why multicellularity evolved on Earth is that it increased the maximal size possible. In nature, size is one of the most important deterrents against being eaten or an enabler of the reverse. This is especially true for microscopic organisms, since they wrap their membranes around prey to engulf it. Therefore, it is advantageous for many organisms, though not all, to increase in size. The problem arises when trying to transport resources throughout the organism. In the case of single-celled creatures, they rely on diffusion, that is to say, particles' tendency to spread out evenly in fluids. But as cells grow, the time it takes for particles to pass through the membrane and arrive at the cell's center will increase. Eventually, the cell's core will starve and die, which entails the same for the rest of the organism. To circumvent this, unicellular organisms on Earth began clumping together, notably with tiny gaps between them. Thereby increasing their total volume while still being supplied through diffusion.
Two types of multicellularity would then form: colonial organisms, which are thought to be the first, and multicellular organisms, thought to be derived from the aforementioned. The difference between them is that each cell in a colonial organism can survive on its own. Multicellular organisms, on the other hand, often possess specialized cells that must cooperate for survival.
On Sighsten, the first organism to evolve one of the above would be colonial Solätare dubbed Plattblad. Thereafter, some Ruttenätare would also develop colonies, thereby becoming yet another colonial organism who will be called Sporspridare. Lastly, some Sakätare would also abandon unicellularity, but instead of several cells cooperating, their cells would specialize. Thereby becoming a multicellular organism. Three new clades would then appear, each evolving multicellularity separately. The new groups are Vattenkropp, Havsfjäder, and Bottenmask.
Two types of multicellularity would then form: colonial organisms, which are thought to be the first, and multicellular organisms, thought to be derived from the aforementioned. The difference between them is that each cell in a colonial organism can survive on its own. Multicellular organisms, on the other hand, often possess specialized cells that must cooperate for survival.
On Sighsten, the first organism to evolve one of the above would be colonial Solätare dubbed Plattblad. Thereafter, some Ruttenätare would also develop colonies, thereby becoming yet another colonial organism who will be called Sporspridare. Lastly, some Sakätare would also abandon unicellularity, but instead of several cells cooperating, their cells would specialize. Thereby becoming a multicellular organism. Three new clades would then appear, each evolving multicellularity separately. The new groups are Vattenkropp, Havsfjäder, and Bottenmask.
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