So, assuming you don't believe that we came from Adam and Eve and that we were in some way descended from non-human primates, it should not come as a huge shock to you that we have some of the same laughing habits as apes. No, it's not that apes can't wait for Anchorman 2 to come out either or are also sad that Phyllis Diller died. But a recent study published in Evolution and Human Behavior indicates that they do laugh at practical joke-type stuff, such as someone slipping on a banana peel (which is much more common among apes anyway). And the way that we laugh -- making sort of weird animalistic honking sounds -- is how apes laugh too.
The study didn't figure out every damn thing about people, laughter, and apes -- gotta leave something for the next study, so you can get more of those sweet, sweet tax dollars. But it suggests that laughter predates language, and, ergo, humans. In fact, laughter plays a social role that may have helped early human communities emerge.