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.
San Francisco: World War II and the Cold War. San Francisco was the main point of embarkation for World War IIâs Pacific theater, and the region became a major arms production center. After Pearl Harbor, the cityâs Japanese residents were forced into internment camps far inland.