Regarding cell-to-tissue/organism transition: I bet
some here have heard of _Salinella salve_. What gives?
Google says this is the monoblastozoon, which, I've been told, probably
never existed (either a misinterpreted observation, or just plain made up).
A cell that's ciliated on both sides would be unique within all of
Opisthokonta. http://www.novelguide.com/a/discover/grze_01/grze_01_00024.html