So who knew, part two...

The term atavism (derived from the Latin atavus, a great-grandfather's grandfather; more generally, an ancestor) denotes the tendency to revert to ancestral type. An atavism is an evolutionary throwback, such as traits reappearing which had disappeared generations ago.[2] Atavisms occur because genes for previously existing phenotypical features are often preserved in DNA, even though the genes are not expressed in some or most of the organisms possessing them. (from Wikipedia). My brother Chris threw this word at us. I’m still not sure what he meant.