Transparent Immortal Jellyfish

Students Christian Sommer and Giorgio Bavestrello collected Turritopsis polyps, which they kept and monitored until medusae were released. It was thought that these jellyfish would have to mature before spawning and producing larvae, but when the jar was next checked, they were surprised to find many newly settled polyps.

They continued to observe the jellyfish and found that, when stressed, the medusae would fall to the bottom of the jar and transform into polyps without fertilisation or the typical larval stage occurring. The discovery, aided by the spectacular nickname 'immortal jellyfish', captured the world's attention.