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When commerce meets an extraordinary being, it asks what the being can extract, not what the being is. Zurita never treats Ichthyander as a person to be understood. He sees a diver who needs no air and can strip pearl beds, so wonder turns directly into a plan for unpaid, captive labor. Novelty in a living thing becomes, to the market, a productivity advantage to be owned.
Look at who institutions put on trial when a new kind of being appears. Salvator is prosecuted on charges pressed by church-aligned interests for violating the natural order. Ichthyander is handled as evidence and as a disputed possession rather than as a rights-holder. The creature's own interests are nearly absent from the proceedings. Moral panic about transgressive science judges the scientist's audacity, not the welfare of the person the science produced.