Spain - Ver la versión original en español - From the beginning of time, barriers to prevent a potential source of danger have been the survival strategy for animals and humans. Some animals still continue using techniques to improve their camouflage and to protect themselves from predators. As control over the environment improved, humans abandoned the strategies of animals to avoid specific hazards. Fences, shields, armour and fortress walls are examples of the methods that men adopted for certain risks. The fundamental goal is to provide an obstacle to a … [Read more...]