Zombie Lifespan

It is generally believed that zombies have an average lifespan of approximately one year. One thing that I have understood is that climate and weather exposure may greatly increase or decrease a zombie's lifespan. The rate of decay is significantly affected by temperature and humidity levels.

In tropical regions where the temperature and humidity are high, a zombie may only last a few days at best. The high humidity and temperatures accelerate decay at a rapid pace, reducing the zombie to a pile of bones in as little as 10 days in some cases. With a high human population in these areas, there is readily enough food/prospective-zombies in the area to keep the undead population high despite the rapid decay rates.

The rate of decay slows down and almost comes to a grinding halt in areas of extreme heat and cold. A zombie can live an existence of many years in the frozen tundra feeding off seals and wandering Inuit (Eskimos). Some zombies caught up in this region have been estimated to be well over 150 years old. Zombies have also been known to live for hundreds, possibly thousands of years in the hot dry areas of Northern Africa and the Middle East. The whole myth of mummies comes from travelers seeing the lone, wandering corpses in the middle of the dunes of the Egyptian Sahara.