Fascinating read!

But Moroz thinks it happened twice — once in ancestors of comb jellies, which split off at around the same time as sea sponges, and once in the animals that gave rise to jellyfish and all subsequent animals, including us. He cites as evidence the fact that comb jellies have a relatively alien neural system, employing different chemicals and architecture from our own. “When we look at the genome and other information, we see not only different grammar but a different alphabet,” Moroz said.

It's definitely a difficult subject and a lot more research will need to be conducted but I am interested in further data supporting the claim.