What is a characteristic feature of the panther mentioned in the text?

A notable characteristic feature of panthers is their solitary nature. Panthers, which are often a reference to black leopards or black jaguars, tend to be solitary animals, preferring to live and hunt alone rather than in groups. This behavior is distinct from many other large cats that may form social structures. Their solitary nature impacts their hunting strategies and territorial behaviors, as they establish and defend ranges that others of their species typically do not intrude upon.

While energetic behavior, strong claws, and loud roars are relevant traits to many big cats, they are not unique distinguishing characteristics for panthers, making solitary nature the most defining feature in this context.