Thank you, @Dreamweaver! 
Recently, I’d been thinking of @Maoshan_Wanderer’s excellent link in a longer post.
This link from the Sapien website may be of interest as well. This is an old article written by Dale Power, Captain_Nemo’s teacher.
https://enlightenedstates.com/2016/07/30/tumo-the-generation-of-metabolic-heat/