Cheating birds, faithful friends and a passion for research

Irene Liu’s talk on “Sperm competition, infidelity and the hunt for reproductive proteins in birds” was as engaging as a really good mystery novel and as informative as your Introduction to Biology textbook. The University Scholars learned about rapid evolution in proteins and slow evolution in dissertation research and writing, about cheating birds and faithful friends and the ways in which energy, persistence and a reliable support group can help you sequence DNA but won’t get you into Cuba.

Irene’s core research question was “Do species with different levels of sperm competition show different rates of reproductive protein evolution?” To arrive at this question, the audience had to learn about the fundamental process through which genetic information is transmitted from DNA to RNA to proteins. Rapid evolution is measured by observing the ratio of non-synonymous substitutions (like the one from AAC to ATC that gives us a different protein) to synonymous substitutions (like from ACT to ACG that gives us the same protein) that occur in proteins when a DNA sequence changes. Sometimes, this accelerated evolution can be a signal of strong selection due to competition or conflict between different individuals. Irene’s question then was whether rapid evolution in reproductive proteins happens in bird species with higher levels of extra-pair mating (a.k.a. cheating), in which sperm from multiple males compete to fertilize a female’s eggs. To arrive at this question, Irene had to first learn that she did not want to watch fruit fly copulation for the rest of her research career, that friends are great sources of academic news and that some supportive faculty members also have pretty cool lives (see the picture of Irene’s co-adviser with Patrick Stewart). If only more researchers were as honest as Irene! Her story of trying to bring her different interests together into a single research topic can serve as a reminder to interdisciplinary and passionate people everywhere that formulating a research question is not just a professional matter – it’s a deeply personal one.

Irene then walked us through the intricate requirements of field research. She learned taxidermy to create an incredibly life-like red-winged blackbird female (or, as she refers to it “a red-winged blackbird blow up doll”). She collected samples of bird semen to bring back to the lab and used Duke’s core facilities like the Sequencing and the Proteomics Facility for analysis. Faced with a dearth of genomic information for blackbirds, Irene learned how to sequence DNA using seminal fluid proteins and RNA as a Rosetta Stone. She showed us how one conducts paternity tests, “when I do it or when Jerry Springer does it” and how rewarding it feels to align sequences of DNA across different species of blackbird. The pitfalls and setbacks in this long process were many and Irene graciously spared us some of the most difficult moments. She did, however, share her experience of being denied entrance to Cuba, showing that even an indomitable spirit like hers can’t overcome every obstacle – particularly when the obstacle has an armed military and an impenetrable bureaucracy.

At the end, Irene reminded us that careful research and years of fieldwork frequently culminate in a few grueling months of dawn-to-dusk lab research, frantic writing and the dreaded dissertation defense. Irene quotes Tina Fey to remind us that perfection must be abandoned as a goal along the way: “The show doesn’t go on because it’s ready; it goes on because it’s 11:30.” But even when the ideal results aren’t there and you don’t find the evidence for rapid evolution that you were hoping to uncover, you can still make a great contribution to humanity’s collective pool of knowledge and have a really great story to tell! And, in Irene’s case, thousands more genes to check for rapid evolution and a fascinating research agenda for her postdoc.

The talk ended with a flurry of questions from University Scholars from all disciplines, graduate and undergraduate alike and a last bit of information and entertainment.  As a group, we were happy to discuss issues related to fundamentals (our Symposium 2015 topic). Graduate students Sam Bagg (4^th year in Political Science) and Bryce Gessell (1^st year in Philosophy) prodded Irene about the mechanisms of evolution, while undergraduates Michaela Walker (3^rd year Pratt) and Tamra Nebabu (2^nd year Pratt) inquired into the fundamentals of classifying birds into different species.

Thank you, Irene, for another awesome presentation!