I think the article says they just haven't tested other cases. I wouldn't expect the symbiotic microalgae to be that picky.
Edit - The article makes Okkef's point, I just missed it.
The article says otherwise.
> Fragments from different species and even different animals of the same species did not fuse together, and so did not nurse the bleached piece back to health.
The article says otherwise.
> Fragments from different species and even different animals of the same species did not fuse together, and so did not nurse the bleached piece back to health.