See subject. Thought of it this morning when self and dog coincidentally shared a moment.
Not sure what constitutes a muscle, though. If its anything contractile, that would include most everything except jellyfish, and I know they don’t stretch. <Right?>
I guess it depends on how hard you pull them.
Dogs and cats do seem to take as much, or more, pleasure in stretching as humans. I’ve seen quite a few big cats do it. I’m not sure if any other species does such an exaggerated job of it, but it would seem that any creature with musculature that can “tighten up” would have some form of loosening movement.
My boy Dane can turn a stretch into a feature film, usually as he’s reluctantly getting off the bed and all too often punctuated with a fart.
Jellyfish have contractile tissue too, and I am reasonably sure it is made of the same basic stuff (actin, myosin) that your, and your dog’s, muscles are made of. I don’t know if they stretch, though. What they don’t have, of course, is a skeleton, or connective tissue connecting muscles to skeleton. I have a feeling that stretching may have something to do with that.
Birds do it.
I’ve no idea, though, whether bees do it, or if educated fleas do it.
I have seen grasshoppers do what appears to be stretching. I can’t say for sure though. My pigeons use to stretch.
That weird leg-extension thing?
I think you’d have to differentiate it from other actions, like mating or warning display, or pheromone-spreading, or such.
As I understand it, you can’t stretch a vertebrate beyond its maximum height/span/reach without injuring it.
Fifty-four page quite beautiful PDF of charts, diagrams, detailed anatomy of jellyfish musculature and kinematics and energetics for their motion.
I always thought the suckers just floated with the current.
OP still open question, though.
Horses stretch. They will do the front-end-down stretch like a dog or cat, and also do a hind leg stretch sometimes after a standing snooze.
When horses doze standing, they ‘cock a hip’, or take all their weight on one hind leg while the other leg sort of knuckles over at the fetlock (ankle). When asked to move from that position, or if they’ve been in a stall all night and haven’t had a chance to move around much, the first few steps are often interrupted while the standing hind leg is stretched waaaay out behind them, and sometimes the neck goes down and out too for maximum pull over their topline. My guy accompanies this with grunts and groans as though his life is just too much to bear 