But why, you may ask, is an evolutionary biologist interested in epigenetics? Because a subset of epigenetic effects turns out to be heritable across generations. This means that there is something else other than classical genes (i.e., sequences of DNA) that both carries information and is passed from one generation to the next. This is big news for biologists (though the suspicion had been around for a while), because it suddenly broadens and complicates — possibly dramatically — our concept of inheritance, with a wide range of consequences for how we understand evolution. After all, the natural variation among organisms so crucial for natural selection to work had been assumed until recently to originate only from changes in gene sequences.