Monogatari no Kuromaku ni Tensei shite ~Shinka Suru Maken to Game Chishiki de Subete o Nejifuseru~ - Vol. 3 Ch. 12

[TennoSoul]

Quite smart

 

[Kdrakon]

Horses rest and sleep standing, no?

 

[Kaarme]

Horses rest and sleep standing, no?

Not only. They rest and sleep both standing and lying down. It would be interesting to know if domesticated horses get down far more than wild ones, since they ought to feel much more safe in the controlled environment, with little danger of wolves and other predators. Probably people have studied it many times over.