Antonyms for "most evolved" include "primitive," "undeveloped," "backward," and "underdeveloped." These words imply a lack of progress or advancement in terms of societal, cultural, or personal growth. "Primitive" suggests a state of being in its earliest form, while "undeveloped" implies a lack of development or growth. "Backward" and "underdeveloped" both suggest a lack of progress in comparison to others. Thus, the antonyms for "most evolved" highlight a condition or state where growth, advancement, or progress has not yet been achieved or has been reversed.