If there were creatures on Uranus - and I don't think there are - seasonal affective disorder would be a lifetime thing.
For the first half of geological time our ancestors were bacteria. Most creatures still are bacteria, and each one of our trillions of cells is a colony of bacteria.
No other creatures of the savannah sleep as deeply or as soundly as lions, but after all, lions are the main reason for not sleeping soundly.
There are, of course, fat characters in books out there, some of them quite enduring and famous. But they tend to be creatures of young-adult or commercial fiction.
I wanted to be a writer from my early teenage years, but I never told anyone. Writers, in my opinion, were god-like creatures, and to say I was striving to be a writer would be incredibly arrogant.