Over 200,000 years ago, Krypton had developed scientific advancements far beyond those of present-day Earth, and had discovered a way to conquer disease and aging by perfecting cloning; vast banks of clones, kept in stasis, held multiple copies of each living Kryptonian so that replacement parts were always available in the event of injury. All Kryptonians were now effectively immortal, "with all the strength and vigor of youth maintained", and for millennia they enjoyed an idyllic, sensual existence in an Arcadian paradise.