Joao Silva/The New York Times  Residents of Ambohimirary, Madagascar, during a ceremony to honor their ancestors.  a) James Watson is actually Wotan, king of the gods.  b) The Valkyrie have been cloned.  Readers who are awake no doubt picked c), because the other possibilities, though attractive, are silly. But Wagner’s heroic four-opera epic, “The Ring of the Nibelung,” is built of motifs (or motives), musical phrases that are associated with various important aspects of the operas, like Wotan, or the ring itself. And the human genome, which is almost as complicated as the “Ring” operas, has motifs as well.  In molecular biology the word “motif” can mean different things, but in the simplest sense it is a kind of genetic phrase. It can be functional, or it can have no significance except that it is passed on from generation to generation so that it can be used in tracking human migrations.  Motifs are also found in visual art, in literature and in the music of many other composers, and the word can refer to an idea, a pattern, a theme — all sorts of things. I had Wagnerian motifs on my mind because I recently saw “Götterdämmerung,” or “The Twilight of the Gods,” which is full of motifs from the other three operas, repeated, modified and woven together. (Later this month and next the Metropolitan Opera is presenting three complete “Ring” cycles.)  The Magic Fire Music (which represents Loge, the trickster demigod) was still in my head when I picked up a population genetics paper on the settling of Madagascar published online March 12 by The Proceedings of the Royal Society B. So the references to the “Polynesian motif” and the “Malagasy motif” caught my eye.  This usage is not new. I e-mailed Scott Gilbert of Swarthmore College, a developmental biologist with broad interests, and asked about the history of the word “motif” in biology. In turn, he asked around and wrote back that it seemed to have been taken from music, and that its use may go back to the ’30s to refer to other aspects of biology.  He noted that one of the founders of embryology, Karl Ernst von Baer, thought that music was an excellent metaphor for embryonic development. He wrote in 1864, "I believe I can compare the various life-processes to musical thoughts or themes and call them creative ideas, which construct their own bodies themselves.”  In the case of the March 12 paper, Murray P. Cox, of Massey University in New Zealand, and his colleagues sampled the DNA of Malagasy people and others throughout Indonesia. In particular they looked at a snippet of DNA called the Malagasy motif, found almost exclusively in Madagascar. This was a slightly changed version of the Polynesian motif, which is found in parts of Indonesia. Their analyses of when and where these motifs were found led to their conclusion of what probably happened on Madagascar. It confirmed the broad outline of previous linguistic and archaeological studies, but provided details on timing and the origin of settlers that had been lacking.  Rather than a planned colonization, the researchers suggest, the first people to settle permanently in Madagascar may have arrived by accident. It seems that Africans contributed their genes to the Malagasy people later.  The motifs Dr. Massey is referring to are not genes that determine what a person looks like or whether he or she is lactose intolerant or susceptible to sickle cell disease. In that sense they are nowhere near as important to biology as Wagner’s motifs are to his music.  But words always bring clouds of unintended meaning with them. I’m glad motifs sneaked through the connotation filter. To me motifs sound elegant, fluid and variable, likely to mix with one another in unpredictable ways, much the way humans have done over our long history.  So the word could have some added value. What if, when tracing our genealogies, we abandoned thinking of ourselves in terms of the constricting and unscientific concepts of racial and ethnic identity, and thought instead about what ancestral motifs resonate in our genome?  Better the complexities of music than the simplicities of black, white and Hispanic (nonwhite) — and, although just a metaphor, biologically closer to the truth.
A study of recurring DNA snippets in the people of Madagascar calls to mind the phrases that punctuate Wagnerâs âRingâ operas.