The oldest species of floating jellyfish has been discovered by scientists in fossils half a billion years old. The discovery, called Burgessomedusa phasmiformis, was made in Canada and is one of the oldest species of floating jellyfish ever found.
The new species of jellyfish is saucer or bell-shaped, up to 20 centimeters tall. It has about 90 short tentacles that allow it to capture large prey. Jellyfish belong to the subgroup Cnidarians, the oldest group of animals known as medusozoans. They are composed of 95% water and decompose quickly, so jellyfish fossils are rare.
Jellyfish fossils were found at Burgess Shale in Canada, an area known for its well-preserved fossils. In the late 1980s and early 1990s, scientists found exceptionally well-preserved remains of various marine organisms, including jellyfish, there.
Jellyfish fossils are rare, so their evolutionary history has been studied primarily through microscopic fossilized larvae and the results of molecular studies of modern jellyfish. The discovery of the new jellyfish species allows scientists to better understand the evolution of these creatures and expand the understanding of ancient ecosystems.
Joe Mojsiuk, one of the study’s authors, notes that the discovery of Burgessomedusa phasmiformis shows that the Cambrian food chain was much more complex than previously thought. This discovery confirms the presence of jellyfish in ancient marine ecosystems.
Jellyfish have a complex life cycle that includes polyp and jellyfish stages. In the polyp stage, jellyfish live on the seafloor and reproduce asexually, and then develop into jellyfish that swim freely and mate with other jellyfish.
The discovery of the oldest jellyfish provides new data for studying the evolution of these animals and expands our understanding of ancient marine ecosystems. This discovery emphasizes the importance of fossil preservation and its role in science.