Jellyfish

Jellyfish are unique in the animal kingdom, possessing no brain or centralised nervous system and instead relying on a diffuse net of nerve cells for movement and communication. This has long made them a favourite among marine biologists - jellyfish are incredibly ancient, with some species having been around since the Cambrian era, approximately 500 million years ago. Jellyfish also have a lot of practical and scientific applications today. For example, jellyfish are a source of many promising pharmaceuticals, as well as a potential source of biofuel. Their slow and graceful swimming motion is also studied in robots in many universities and research labs and jellyfish-inspired designs are used in propulsion systems of autonomous underwater vehicles.