When did the comb jelly evolve?

about 515 million years ago
Evolutionary history. Despite their fragile, gelatinous bodies, fossils thought to represent ctenophores – apparently with no tentacles but many more comb-rows than modern forms – have been found in Lagerstätten as far back as the early Cambrian, about 515 million years ago.

Where did comb jellyfish come from?

Comb jellies have since arrived in the Caspian and Baltic seas, as well as along the coasts of Sweden. As of 2013, the American comb jelly was listed by the Global Invasive Species Program among the World’s Worst Invasive Alien Species.

How was the comb jelly introduced?

How the comb-jelly (Mnemiopsis leidyi) is spreading through European seas (invasive species) The most threatening event for the Caspian ecosystem was the arrival of the North American comb jelly (Mnemiopsis leidyi). It was brought accidentally to the Caspian in the ballast water of oil tankers.

How did jellyfish evolve?

Jellyfish come from one of the oldest branches on the animal family tree, the phylum Cnidaria, which includes corals and anemones. At some point in their evolution, jellyfish gained the ability to transition from a stationary polyp to a swimming medusa.

How did the comb jelly go extinct?

These defense mechanisms didn’t make it into modern comb jellies, however. This suggests that they may have been part of “unsuccessful evolutionary experiment” during the Cambrian explosion, Ou says. “This major [animal] branch might have struggled a strenuous life.” And eventually, they went extinct.

Who discovered the comb jelly?

The Benthic comb jelly was discovered off the coast of Japan at the Ryukyu Trench. It was observed by the remotely operated underwater vehicle Kaikō on a dive into the Ryukyu Trench in April 2002, but the video and images of this unique bottom dwelling ctenophore remained “undiscovered” until several years later.