One of the fallouts of aging is recognised to be the inability or reduced ability to appreciate humor and sarcasm. When we talk of humor we talk about humor in situations as well as in dialogue. For example most old persons will not be able to supply a punchline to a joke. Likewise ,the ability to understand the nuances of a typically humorous situation may diminish as part of the general reduction in cognitive faculties experienced by old persons.
Similar thing seems to be happening in the case of people suffering from developmental disorders. Humor is one of the highest traits of the fully evolved humans .Humor and wit are used by young men and women to attract their mates .