Ty the founder of the Circle is finally seen when the Marianas Trench ecosystem comes together, even though he has been seen all throughout the book by being Kalden. The secrecy surrounding Ty can be equated to the seahorse. Immediately when the seahorse was added to the tank, it hid. This is much like how Ty went into secrecy shortly after creating the Circle. This seahorse already knew the dangers that could come, which makes me wonder if Ty had already seen the dangers that the Circle poses right after he created it. The seahorse also had many children, like how Ty has many workers.
The children of the seahorse seemed to just move around mindlessly, without any real direction. While the see horse moved, knowingly to become hidden, like Ty. The children of the seahorse are the workers of the Circle, not knowing exactly what is going on or their purpose but still moving around and marveling at the Circle's progress. This shows just how different the mindsets of the Circle's workers are as compared to its creator. At this point, Ty needed more help so he turned to Bailey, much like how the octopus was added into the tank.
The octopus is without a shadow of a doubt Bailey. All the octopus wanted to do was get to know everything, from its new home to all of the other inhabitants. This is much like Bailey, who wanted to get to know everyone in the Circle. The octopus also tried not to hurt anything, such as the many seahorses, like how Bailey tried to never hurt anybody's feelings at the Circle. The idea of the octopus expanding in size can be related to Bailey because his personality grew to try and include everyone. This can also be seen because Bailey would always be known in any room he enters, like octopus expanding to fill any container it is put in. Bailey is only the second of the Wise Men, the third came in the form of a shark.
Stenton, the business mind of the Circle, is the shark. He is completely enthralled by everything the shark does and does not every look away from it. He is by far the most ruthless of the Wise Men, and the shark is 100% ruthless. The shark is also very transparent, literally, while Stenton is very straight forward (transparent figuratively). Stenton was blunt and told people exactly what he thought, like how all of the shark's digestion could be seen. Also, the shark destroyed everything in the tank. This could symbolize how Stenton's greed will be the downfall of the Circle. The Shark destroyed the octopus, much like Stenton could take down Bailey, who is too nice to fight back. Then, once the octopus is out of the way, the shark went after the seahorse and quickly ate it, like how Ty is quickly incapacitated from trying to stop the completion. This all leads to the destruction of everything in the tank, or symbolically, the Circle.
The Mariana's trench creatures were very important in showing just what was going on in the book. Each of the Mariana's trench creatures personified their respective Wise Man and showed just how the destruction of the Circle will come apart. It seems that once the completion happens, like the completion of the ecosystem, nothing will be safe from the destruction.