I'm not entirely sure what you mean, but a fit animal is one that is able to out-compete with other animals in its ecosystem. It possesses some kind of advantage, which makes it easier to compete with others for food, water, shelter, and mates. Due to these qualities, the animal is obviously able to live for a good deal of time and have a greater chance of producing viable offspring.
The process is called ovulation
What is the question exactly??
Over time, rain and weathering causes rocks to release phosphate ions and other materials. This inorganic phosphate is then distributed into the soil and water. plants take up inorganic phosphate from the soil. the plants may then be consumed by animals. Once in the plants or animal, the phosphate is incorporated into organic materials that break down organic matter to inorganic forms of phosphate. this process is known as mineralisation. Phosphate in soil can end up in waterways and eventually oceans. once there, It can be incorporated into sediments over time.