Starters are endangered species because they are the most caught species by trainers of that region due to their convenience and utility, as top tier common species.

They started evolving antropomorphic with time because of their constant human contact, thus replicating and symbiosis of their human masters.

This is why they start mimicking human-like things and professions. A fuecoco probably got mostly caught by people that do music and evolved to sing. Inteleon got caught by spies and federal agents or kids with water guns.