Brain comb jellies tell more about the origin of neurons

Neurons, the cells in our nervous system that specialize in sending and receiving information, are perhaps the most complex cells there are. But how were they born?

Opinions are divided on this subject, but Japanese researchers believe they have found the answer. They dived through time and under deep water, where they observed primitive animals from the lineage of jellyfish and anemones and that of the comb jellyfish. Of the four lineages from which more complex animals eventually evolved, only animals from these two lineages possess neurons.

However, between these two lineages, there are also differences in the way these neurons are assembled. Do neurons originate in two lines, separated from each other? To find out, the researchers studied the proteins, cellular structures and genetics of the two lines using the very latest techniques. They saw enough similarities to conclude that the neurons are more likely to have appeared only once.

They also discovered possible precursors to the neurons we know today. And this in turn raises whole new questions: why was it necessary, for example, to switch from these neurons to more complex variants? And how exactly did those very first neurons work?

Read more: Inside the brain of comb jellies: Scientists explore the evolution of neurons.