Comb jellies, or ctenophores, are unique among animals, having been the first group of animals to branch off from the rest of animals.
This evolutionary uniqueness makes them ideal for studying the evolution of neural development and neural pathways. While ctenophores don’t have what we would think of as a brain, they do have nerve cells that are connected together throughout their bodies in a web-like “neural net.” Understanding these strange nervous systems will give scientists clues about the vast range of possible nervous systems in evolution and perhaps even about how our own brains evolved. Allen Distinguished Investigator Joseph F. Ryan, Ph.D. is part of a team studying these ancient creatures’ unique nervous systems.
Easy, breezy, mucusy comb jellies are a modern-day wonder. At a glance, they might resemble what we call jellyfish, but they’re not the same thing. Jellyfish and comb jellies are part of two different phyla, Cnidaria and Ctenophora, with two very different evolutionary histories.
Comb jellies are a diverse group of species categorized by their distinct physical and genetic differences. Residents of every ocean, they can be found in glowing rainbow hues, peculiar shapes, or sometimes in the mouths of other jellies. Unlike many other animals, climate change is making them destructively bloom in some areas. When competitors slowly disappear from an area or fertilizer run off leads to an abundance of plankton, ctenophores are not shy to establish dominance.
