The two populations of interest on Heart are the Reds and the Pinks.
These creatures are unique on their planet, as they have evolved quite
miraculously from microorganisms. It is suspected that the first Red
or Pink ever was an extreme mutation of a gene that made a
microorganism grow into a macro one, practically overnight. Such a
thing would be almost entirely inconceivable in any other ecosystem,
but very few other explanations can be given as to why there are so few
life forms on Heart of macro size. The theory of evolution on Heart
is, actually, very likely despite the improbability of the proposed
theory. The anatomy of the Pink and the Red is more similar to that of
a very large cell than any animal on, say, Earth. The flesh of a Red
or a Pink is more of a membrane than skin, and it is permeable in parts
to allow for nutrient consumption. The “hands” of a Red or a Pink
consist of tubes that are permeable nutrient intake. These creatures
of Heart eat by absorbing microbial nutrients in their surroundings.
This is why the population is so small—the planet can only support
enough organisms as can naturally absorb from the planet’s surface.
The surface of heart is rich in microbial species that naturally become
absorbed when a Red or Pink sticks it’s “hands” to it in order to fuel
their systems. In return, Reds and Pinks give off other nutrients when
they move from their lower body that support the environment and allow
for microbial reproduction.