At Gene Expression, Razib Khan considers the rise of epigenetics. Using Google Scholar, he searched to see how often the term was searched for between 1999 and 2009, as compared to "sexual selection" and "genetic drift," all concepts that he has considered to be "scientific deus ex machina." In addition, Khan searched for those terms in Google Blog Search, though he notes that there was a concurrent rise in the number of blogs during those years.