In relation to cats, dogs and other animals, what is "splooting"?

When a cat or dog sploots they are relaxing their back legs flat behind them. This helps stretch the muscles of the legs and back and some call it yoga for cats. For dogs, it might be a bit more complicated as they might be relaxing, showing trust by being in a vulnerable position, or could be taking up space to show dominance. Either way, it probably feels good! Other mammals may sploot for similar reasons as listed for the dog and cat.

https://www.floppycats.com/what-is-splooting-and-why-do-cats-do-it.html
https://www.thedodo.com/dodowell/why-do-dogs-sploot

Aside from just being an adorable word, "splooting" is a posture that four-legged animals sometimes adopt. They lie prone (on their stomachs) with their limbs spread-eagle on the ground. Two reasons animals may sploot is to rest in a relaxed position, and to cool down on a cold surface on hot days. Many animals do not have one of the cooling mechanisms that humans take for granted - sweating - and instead rely on panting or external cooling sources.

Dogs and cats are common splooters (at least from a human perspective), but other animals noted to sploot include squirrels, polar bears and marmots. It seems to be the exclusive domain of mammals - invertebrates reptiles and amphibians are natural splooters in their baseline posture, birds are two-legged, and fish don't have legs.

https://en.wikipedia.org/wiki/Splooting
https://www.theguardian.com/us-news/2022/aug/11/city-tells-new-yorkers-dont-panic-about-splooting-squirrels