Octopuses are known for their ability to regenerate their limbs. In fact, they can regrow a new arm if one is lost or damaged. This process is known as regenerative ability.

The octopus has a unique regenerative ability because it is able to regrow not only the arm, but also the complex structures within the arm, such as the suckers and muscles. This is a remarkable feat, considering that the octopus arm is a highly specialized structure with many different functions.

The octopus's regenerative ability is due to the presence of stem cells in its body. Stem cells are cells that have the ability to divide and differentiate into various types of cells, including muscle cells and nerve cells. When an octopus loses an arm, these stem cells are activated and begin to divide, eventually forming a new arm.

The process of regenerating an octopus arm takes several months to complete. The octopus must molt its old skin in order for the new arm to grow. During this time, the octopus may appear sluggish and may not be able to move as quickly as it normally would. However, once the new arm has grown, the octopus is able to regain its full range of movement and continue on with its normal activities.