I suppose it's weird that the fish thing was dropped, but on the other hand, I think it's more hinted that, unless they have an actual cry, then the humans can't communicate with them. Snakes for example, no one can communicate with them except Tarouza due to his special skill. And I guess, when charging into the tower of babel, it's hard to bring aboard some fish with them.
And after Monoko leaves the story, I guess at that point you really do have to have the story drive to Tarouza going to the Tower of Babel. To be honest, I really would have liked a story that was a bit longer that did more of the earlier expansion on animal families and stuff, but considering that we've been in the adult part of the story for literally half of the lifespan of this manga, I think it's fine.
Yes, it's a bit clumsy at the end, and it would have been nice to see Jyuu as an adult show up before the second to last volume, but it's neat. And honestly, the UFO discs and lasers might be really over the top after all we've been through, but he had to have found something beyond our reckoning considering there are still remnants of human civilization hanging around here and there for 10000 years. It was a nice callback to Konjiki no Gash!! too.
Elaine's case is the one that really perplexes me though. I think I'm fine with Kuou becoming really reclusive and depressed that he's the last of his species on the planet, but with only a few flashbacks, it really doesn't make much sense to empathize too much with his letting a maniacal guy like Giller into the tower of Babel. I can reconcile that probably, whatever human entered the tower first was probably made babelmaster in Kuou's absence, but I'm not sure how Elaine obtained an ego if Giller wasn't involved in her creation. It's a funny case, to be sure. Hinted in scenes of Kuou in volume 7 or so, where Kuou's crying in front of Elaine, but it was just a really random turnaround that it would've just been good to keep Kuou as basically a "Dr. Light in Megaman X" sorta figure.
Regardless of the fish, though, I think the other question I have is certain things about the miracle children
- What's with the infinity symbol on Tarouza's basket and Capri's necklace?
- Will we ever find out why Tarouza's mother dumped him off in the river?
- Each of the miracle kids seem to have some special thing about them for the most part. Tarouza can connect consciousness, Giller's super smart and has a God-given gift of creating an ego, Jyu has an air of violence to push evolution, Riemu seems to have a near-photographic memory (probably hinted through the brief panel flashback that she's a kid of a super smart scientist). So does Capri have anything special besides getting along with carnivores?
All in all, I really do enjoy the package, and even if the second half of the story isn't as heartrending as the first half, it's just got so much weight from the beginning that there's a lot of payoff to be found in the second half with a cast of colorful animals coming together to change the world.