In a medieval high fantasy world where magic exists, if there is a geographic area in which living creatures mature and then stop ageing; what would the negative effects of this be; firstly on a small scale, and secondly if it affected the whole world?
Here are the rules:
- There is a spherical area that is causing creatures who enter it to stop ageing once they've reached maturity. They can theoretically live forever.
- The creatures are not invulnerable; they can be killed, and they still need to eat and sleep. They simply mature and then don't age.
- We don't know exactly what is causing this phenomenon, just that it's happening.
- Any creature that spends enough time (say, a few days) in the area gains the effects, and retains them until they leave; they then go back to normal after a few days.
- The area is currently localised to a few hundred acres of a forest, but is spreading at a rate of several metres per day, and can cross bodies of water (affecting things in the water) and go through physical objects etc.
The negatives I've thought of so far are:
Plant and animal populations going out of control and overpopulating the area.
Animals becoming brain dead due to reaching their mental capacity, but their bodies are forced to live on; they just lie around undecomposed.
From Alexander's answer: Due to the same individuals continuously reproducing, the gene pool will slowly become stagnant and inflexible, meaning creatures will be less resilient to new strains of diseases or changes in the environment etc.