Why do archaebacteria live in such hostile environments?

Answer 1

Archeabacteria (archea meaning old), was among the first life to live on the earth during it's formation. When the earth was formed, it was covered in molten lava and barely had an atmosphere. The archeabacteria lived in this hostile environment and developed chemosynthesis which allowed it to product food from the chemicals (sulfur, iron, etc.) from the molten rock surrounding it. When the earth cooled down, archeabacteria began to evolve and created bacteria, however some archeabacteria still exist in this world and stays in it's natural environment, the hostile, very hot environments which first created it. Also, they still use chemosynthesis and it may be possible that they require the hostile environments to survive due to the sulfur and iron that is plentiful in those areas.