Professors Brian Masters, left, and Scott Johnson, right, are engaged in one of the most comprehensive genetic selection studies ever undertaken.

Grant funds have allowed Masters and Johnson to pursue a second, related study on extra-pair mating in mountain bluebirds in northern Wyoming. They're exploring whether the male bluebird's coloration affects his paternity success – that is, are females more faithful to bright blue males because they perceive such males to be of high quality?

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Adultery is for the Birds

Adultery is for the birds

TU professors Masters & Johnson study their cheatin' hearts

Birds of a feather don’t always stay together–sometimes they “cheat” on their partners. But scientists believe this adulterous behavior could give their offspring a genetic advantage.

Towson University biology professors Scott Johnson and Brian Masters have a three-year $241,777 grant from the National Science Foundation to find out if baby house wrens born to adulterous females end up with “better genes” that produce a stronger immune system. Additional funds were obtained from NSF to engage undergraduate students in the research.

The TU professors are working with three researchers at Illinois State University to sample the DNA of baby wrens in more than 600 nests to identify those offspring that females produced through the avian equivalent of “extra-marital” liaisons. They will then compare these offspring to offspring that were fathered by the female’s social partner. The study is called “Extra-Pair Mating in Birds–Trading Up Genetically to Enhance Offspring Health?” The work is slated for completion in July 2006.

Like humans, male and female wrens form pairbonds, bird “marriages” of a sort, to reproduce and care for their young. And like humans, wrens sometimes mate outside of the “marriage.” In birds, this is called “extra-pair mating” rather than adultery. While the benefits of extra-pair mating are clear for males – it is a fast and easy way to increase their numbers of offspring -- the advantages to females are less obvious.

One theory is that females engage in this behavior to improve the quality of the young they produce. Masters and Johnson believe that the female wrens seek matings with extra-pair males who offer genetic traits not available in their own mates. They call it the “tall, dark stranger effect.” And they speculate that females may select extra-pair mates in such a way as to increase the likelihood their offspring will have stronger immune systems, and be more resistant to diseases.


	Jessica Brubaker with a male mountain bluebird.

Students Gain Research Experience

For Jessica Brubaker, studying the mating behavior of birds has taken her from Smith Hall’s research lab to northern Wyoming. She’s one of five TU undergraduates working on the project.

The opportunity to do research in Wyoming was an "amazing experience" for Brubaker, who is double majoring in animal behavior and psychology. "Doing fieldwork is a challenge in so many ways (like having to get up at 5:30 a.m. in a mix of snow, hail and rain to go out and work), but it is also very rewarding," she adds. "I really enjoyed working with the birds, monitoring their nests and seeing the nestlings hatch and grow from tiny helpless babies into little copies of their parents over the course of just a few weeks."

Now back on campus, Brubaker is often in the lab – preparing and analyzing DNA samples collected during the summer field season. Also involved in the lab work are students Crystal Neely, Karen Haberstich, Heather Egner and Cristy Ricaurte. The students typically spend from seven to 12 hours a week in the lab, supervised by lab manager and technician Bonnie Johnson.

"Involving undergraduates in research is a primary focus in TU’s Department of Biological Sciences," she notes. "We've been fortunate to have a team of dedicated students to assist us. We’ve analyzed more than 2,000 DNA samples over the past two years, and their help has been invaluable in meeting project deadlines. But even more important, we try to ensure that our students have experiences that prepare them for careers in science."

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