Bohemians live in alternative spaces, these are places that are not normally considered suitable for living in. They don't make wealth their priority. Money is only a means of survival, so they can live for their arts/craft/music/literature...etc.
What causes ice-ages? Fluctuations in the amount of insolation (incoming solar radiation) are the most likely cause of large-scale changes in Earth's climate during the Quaternary. In other words, variations in the intensity and timing of heat from the sun are the most likely cause of the glacial/interglacial cycles.
The Ice Age commenced and continued until the oceans gave up their excess heat and the atmosphere cleared. Water trapped as ice on the continents lowered the sea level by an estimated four to six hundred feet, no doubt exposing the continental shelves. During the Ice Age, all the continents were probably connected by land bridges.