(written at a previous date)
Dear Harriet Walter,
I wonder what it was like for the Little Mermaid when she was enchanted and turned from a half-fish ectotherm into a fully human endotherm?
She'd know about heat and cold from different ocean currents and basking on rocks in the sunshine, of course, but it'd be so different once she was human.
She'd have gone from never producing any of her own heat and mostly staying the same temperature all the time in the ocean (with the occasional change depending on the aforementioned environmental variables) to having this fire inside her, all throughout her body, all the time. Can you imagine how weird that would be? She would sweat when she ran. She would discover the magic of hot cocoa. She would finally understand blankets.
It would be like a kind of thermal puberty!