Yes, they definitely do. See the relatedlink listed below or more information:
No, dolphins have a bone-based skeletal system.
Bottle nosed dolphins are mammals and they do have a back bone.
The name of mid hand bone is metacarpal. These are five in number in each hand.
The longest bone in the human hand is the metacarpal bone, located between the wrist and the fingers.
Dolphins
The lunate bone is a carpal located in the hand.
The ulna doesn't ve any contact with any bone from the hand
The metacarpal bones in the palm of the hand carry and support the hand. There are five metacarpal bones in each hand that connect the fingers to the wrist.
Bottlenose dolphins have appendages similar to many mammals. They have adapted to swimming even though the bone structure is the same.
One symptom of a left bone crack in your hand is severe pain. Also, the inability to move your hand is another symptom.
It is because the first animal to have a hand had a specific bone structure in that hand that was very well adapted. All vertebrate animals with a hand, wing, or flipper trace ancestry back to that first animal with a hand. The bone structure is modified slightly for each animal, but the organization of bones in the hand is the same among all the animals that have a hand.
They are called metacarpals