<span>A trait that improves the fitness of its bearer, compared with individuals without the trait.</span>
The carbon atom has unique properties that allow it to form covalent bonds to as many as four different atoms, making this versatile element ideal to serve as the basic structural component, or “backbone,” of the macromolecules.
No they don't
For example humans. Technically humans are place below a wild predators such as sharks in trophic levels.
But the fact is we can eat sharks. So , organisms don't always stay in the same level
A pituitary glad tumor releasing too much hormones
Usually under ground springs, or sometimes hollowed earth beneath solid earth where the water pools.
