A picture of Sugar lying on her side in the grass, seemingly fake sleeping, can be seen in the original viral tweet by user Jim Rose. The account owner continues by claiming that Sugar detests being ridden and that if a saddle is brought up to the mare, she will lie down and pretend to be a sleeping horse. Sugar reportedly won't open her eyes until the riders have left.

The tweet has received nearly 40,000 retweets and 433,000 likes, as many people have discovered Sugar to be their spirit animal.

There were a variety of responses, with some users praising Sugar and one commenter claiming that it is the horse equivalent of giving one's opinion and then walking away.

Another comment emphasized that even horses understand non-violent opposition and how to pretend to be asleep to avoid doing menial labor. Later, the mare received praise from the same commenter for its excellent non-compliance and for continuing to be unruly. Later, she refers to the mare as "Comrade Sugar."

Since they had never seen horses lying down unless they were dying, other users urged Sugar to get up out of concern that the mare might be dying.

Following that, some tweets claimed that the image of Sugar was just a stock photo and that people who were familiar with Rose's feed would not photograph a mare lying on its side.

Read also: Human Emotions Affect Animal Welfare for Horses, Pigs - Study Confirms 

Stay Apparatus

Horse lovers who responded claim that horses do lie down to sleep. According to Dr. Susan Hazel, a specialist in animal behavior, the propensity is more prevalent for the species during deeper, or REM, sleep.

Horses first appeared in the open plains, according to Hazel. They needed to be able to detect a predator or another animal that might eat them quickly because they are a prey species or one that other animals eat.

They could get their rest or sleep while standing up, but if they spotted a predator, they could easily flee. One of the reasons horses run so quickly is to escape. The horses that were fastest in the early going had a better chance of surviving.

The way horses rest while standing up is what I find most fascinating. Horses have a unique configuration of ligaments, tendons, and the muscles and parts that attach them to the bones. This animal behavior is known as the stay apparatus.

Horses can stand on three legs while resting the other one thanks to the stay apparatus behavior. They can switch which leg they rest on to allow all of their legs to rest. A horse's legs need to rest because they can weigh more than 500 kg.

Horses can sleep standing up, but according to scientists, they still need to lie down every day to sleep. Your sleep patterns vary throughout the night. Everyone goes through different stages of lighter and deeper sleep, and horses are the same.

Only when horses are lying down can the deeper stages of sleep be observed. For our brains to function properly, both humans and horses must experience deeper stages of sleep.

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