Deep-sea waters are warming due to heat waves and climate change, and it could spell trouble for the oceans' delicate chemical and biological balance. However, a study published in Proceedings of the National Academy of Sciences demonstrates that the microbe Nitrosopumilus maritimus may already be adapting well to warmer, nutrient-poor waters. Researchers predict that these surprisingly adaptable iron-dependent ammonia-oxidizing archaea will play an important role in reshaping ocean-nutrient distribution in a changing climate.