[CaptainMarvel]

Wear clothes - I know that hermit crabs wear shells

Make music - I know that birds sing, and a quick Google search shows whales and seals seem to make "music" as well

Theorize - Depending on what you mean of course (but I agree with you about e.g. scientific hypotheses to be tested), but as an example apparently birds "theorize about the minds of others", again by Google search

Writing - Definitely a stretch here (and so I agree with you) but animals do leave chemical markings for others

[andsoitis]

> Wear clothes - I know that hermit crabs wear shells

You show me one outfit, I raise you an entire textile, clothing, and fashion industry allowing us to show our features in displays of status all the way to enabling us to walk in space.

[wizzwizz4]

Sounds like industry is the unique part, then, not clothing.

[burnished]

So a difference in degree then, not kind

[andsoitis]

Both degree and kind. While hermit crabs and other animals who wear garments do very little manufacturing (they use something as is or do some “minor” fashioning), the techniques and kinds of clothes we make are of a totally different sophistication. Our clothes allow us to enter ecosystems and hostile environments, for example. Our clothing is both functional and cultural. Etc.

[dwighttk]

Wear items of clothing that aren’t scavenged detritus

Compose music