# An emerging clock mechanism in a hydrozoan jellyfish

## TL;DR

A new study shows that a jellyfish species uses an internal clock, not just light, to control when it releases eggs.

## Contribution

The study identifies a novel endogenous clock mechanism for gamete release in a new hydrozoan jellyfish species.

## Key findings

- Egg release in the jellyfish is governed by an internal clock.
- The mechanism operates independently of external light cues.
- This finding expands understanding of reproductive timing in marine organisms.

## Abstract

The timed release of gametes is an important feature of marine organisms, and in hydrozoan jellyfish is usually controlled by light. A recent study in PLOS Biology reveals an emerging endogenous clock controlling rhythmic egg release in a novel hydrozoan species.

In hydrozoan jellyfish, the timing of gamete release is often coordinated by light. This primer discusses findings from a recent PLOS Biology article that elucidates a novel, endogenous clock-based mechanism that governs egg release in a new species of jellyfish.