Japanese Green Syllid Worm's Unique Reproduction: Detached Posterior Part Swims to Find Mate

Researchers from the University of Tokyo reveal the developmental stages of the detached part, known as the stolon, including the formation of sensory organs and a 'brain'.

The Japanese green syllid worm, or Megasyllis nipponica, has a unique reproductive process called stolonization, where the posterior part of the worm, full of eggs or sperms, detaches and swims away to find a mate.
The detached part, known as the stolon, develops its own eyes, antennae, and swimming bristles, becoming an independent entity.
Researchers from the University of Tokyo have discovered that the stolon's formation begins with the maturation of gonads, followed by the formation of a head, sensory organs, and swimming bristles.
Before detaching, the stolon develops new nerves and a 'brain' to behave independently.
The study also revealed that head formation genes, usually not expressed in the middle of the body, are highly expressed in the middle of the posterior end of the worm during sexual maturity.