3. Planarian Flatworms
Planarian flatworms possess remarkable regenerative abilities, enabling them to regenerate entire bodies from small fragments. This extraordinary capacity is attributed to their abundant pluripotent stem cells, known as neoblasts, which can differentiate into all cell types, including neoblasts themselves. (journals.biologists.com) These neoblasts are distributed throughout the planarian’s body, comprising up to 30% of all cells. (jove.com) This continuous stem cell renewal and regeneration process effectively prevent death due to aging, allowing planarians to maintain their vitality indefinitely under optimal conditions. (phys.org)