This nest building behavior is instinctual for male bettas and it is not necessary to have a female present to observe your betta building his nest. Most males will blow bubbles but the rate and size of the nest seems to depend on the individual male and possibly, other factors like age, health and water parameters.
Berlin was always the centerpiece of the Cold War and, more often than many remember, very nearly the front line of real combat. At the end of World War II, the city was divided into four sectors, each occupied by one of the four allied armiesâU.S., Soviet, British, and French.
History of the Cold War. The Cold War (1947â1953) is the period within the Cold War from the Truman Doctrine in 1947 to the conclusion of the Korean War in 1953. The Cold War began almost immediately following World War II and lasted through most of the 20th century. 1 Creation of the Eastern Bloc.