Which of the primates have arms with a full range motion?

While it's tempting to say that all primates have arms with a full range of motion, it's not entirely accurate. It's more accurate to say that primates have a greater range of motion in their arms than many other mammals, due to their evolutionary adaptations for climbing and swinging. However, there are subtle variations among species.

Here's a breakdown:

* Most primates: Possess a wide range of motion in their arms, allowing for activities like brachiation (swinging from branches), climbing, and using their hands for manipulation. This includes monkeys, apes, lemurs, and tarsiers.

* Certain species: Have more specialized adaptations. For example, some ground-dwelling monkeys have less flexible arms compared to arboreal species.

* Humans: Have a unique arm structure. Our arms are primarily for manipulation and walking on two legs, leading to a slightly different range of motion compared to other primates. We have a more restricted shoulder joint, which allows for greater precision in hand movements.

Therefore, it's more accurate to say that primates have a wide range of motion in their arms compared to other mammals, but with variations based on specific adaptations and lifestyle.