The Mother Cell is a vector that Reiden Global used in all of its products that caused rapid mutation in animals, insects, arachnids, etc and eventually some humans as well though it also upset the natural balance of the world, forcing animals to no long eat each other which could potentially harm them as well since the carnivores would no longer be eating the herbivores, though this fact did not seem to have any lasting problems from the facts, given in season two by how strong and thriving they all were despite humans taking better precautions to protect from the animals, limiting humans as a food source.