Why are sponges non-conformists to the five kingdoms?

Question

Why are sponges non-conformists to the five kingdoms?

Answer 1

I've no idea, seeing as they belong to the kingdom of Animalia.  They're members of one of the classical five kingdoms, a rather outdated concept that doesn't really work for lots of single-celled organisms.  It works well enough for animals including sponges, though.

Answer 2

I am not too knowledgeable with biology in-depth but I do know that sponges grow slowly and sensitive to its environment.  the slightest change can kill it.  That is why many of them are dying off because of the water slowly becoming more acidic.  same with phytoplankton and zooplankton.  Say good bye to Spungbob!