One should not assume that I am an expert on every topic to which I've contributed, or that I've contributed to all of my areas of expertise. It's way more random than that. (Variety is the spice of life!)
I stumbled onto the origins of language page and am completely fascinated by it, even though there are parts I didn't understand. For example, the article states that
[s]ome scientists believe that Homo sapiens did not leave Africa before [acquiring speech], because they had not yet attained modern cognition and language, and consequently lacked the skills or the numbers required to migrate.
Are they suggesting that Homo sapiens did not emigrate out of Africa earlier because they were unable to stop and ask for directions?
I often get comments about the wide range of topics in my list of contributions. Well, variety is the spice of life, and if you want to spice up your life then you can try patrolling recent changes here at Wikipedia! Not only will you be making a valuable contribution to the world's biggest collaborative encyclopedia but you will also learn new and often off-beat things -- and you will also get a glimpse of the sometimes childish and sometimes amusing antics of some of our newer editors! It is important work, as you can help to fight vandalism, yet it is a lot easier and requires less expertise than patrolling new pages.