posterior epitoke in heteroneries

Hiii Sonali,

In some species of marine worms reproductive activity is in sync with lunar cycles. At breeding time the body of both sexes differentiates (https://www.merriam-webster.com/dictionary/differentiates) into two regions, an anterior atoke and a posterior epitoke (https://www.britannica.com/science/epitoke) , in which gonads develop. When the moon is in a specific phase, the epitoke gets separated from the  body and swims to the surface. The female epitoke apparently moves the male epitoke to release sperm, and sperm release, in turn, evokes removal of eggs. Fertilization process is external. This phenomenon is so well coordinated that a large number of epitokes appear on the surface at about the same time.

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