Millenia is devided into two biodomes. One which is all lava rock, due to it's volcanic irruptions on one side of the island. there is no vegetation or creatures in that area. Who would want to live or grow is this type of environment. The creatures stay away. Smart haa!
On the other side of the island and the other islands you will find the vegetations and the creatures. On the Center of Millenia you will find the mist tropical heart of our planet. Within that mist creature evolve and come out to survive. In order for the creatures and plants to survive, they must know to produce, consume and decompose to generate energy in order to survive and maintain their state of mind otherwise they will become a food source for other creatures of Millenia.
As planet Millenia evolved, vegetation was and is the main form of life form. With all the different types of vegetations that are all over Millenia, the creatures are starting to survive and live in the islands. Millenia is good on the population of the creatures due to their instinct and hunger to survive.
In order to survive the plants and creatures must
have what they need in order to survive in Millenia's atmosphere. 
The
atmosphere is compose of oxygen (respiration for the creatures and plants),
carbon dioxide (for photosynthesis) and Water. Along with the atmosphere,
the plants need good soil to provide all the nutrients to the vegetation,
which will help to create home environments, structural medium in which
creatures and plants can live together. The creatures do not eat or destroy
all the plants. They survive and need some of the vegetations in order to
survive.
The cocoa trees, fig trees, sunflower, orchids
and other vegetations are the most common food source for the creatures
of Millenia. 
Not only do the creatures eat the vegetation, but also
eat other creatures and that is how the population stays under control.
Most of these vegetations are sweet and that is what attracts some if not
most creatures. This type of plants are found close to the ocean where the
sun shines, since some require sun light.
In Millenia's tropical island, you will find soil, rain, plants, and creatures, which produce and reproduce home environments and nutrients to survive in our planet of Millenia. They all must work together, to keep Millenia in tact with all the survival necessities to survive in Millenia.
All pictures on this page are from http://www.osman1.com/tr-quick.html