Earth warming will presumably not lead to a permanent El Nino state in the South Pacific Ocean. This is the conclusion drawn by an international team of researchers after it investigated 50-million-year-old clam shells and wood from the Antarctic. The growth rings of these fossils indicate that there was also a climate rhythm over the South Pacific during the last prolonged interglacial phase of the Earth's history resembling the present-day interplay of El Nino and La Nina....