Genetic Research

Coverage of latest genetic research:
Quirks & Quarks. CBC Radio. Interview aired September 13, 2003

Discovery Channel Canada
Male baboons as fathers by Rob Stein. The Washington Post. September 15, 2003.
Baboon brawls bring out fatherly bonds by Steven Schultz. Princeton Weekly Bulletin. Oct. 6, 2003.

For years, we watched the baboons without ever doing any genetic analysis of them. We knew quite a lot about them through just simple, unobtrusive observation. However, while we could identify with great accuracy all the offspring a female had (so we knew how maternal families were put together), we didn't know anything about relatedness through fathers. And we could count how many consortships a male successfully formed, but we couldn't tell how many offspring he actually fathered.

All that started to change in 1989, when we collected our first blood samples of the Amboseli baboons, through darting. Through analysis of microsatellite DNA, we were able to begin assigning paternity, and identifying relatives beyond the close maternal ones.

Since the early 1990's, our DNA analysis has depended almost entirely on DNA that we extract from baboon feces. The collection of fecal samples in the field is very labor intensive and probably rather comical to an outsider. Every defecation becomes the object of intense scrutiny and researchers rush at the feces, test tube in hand, as soon as the "donor" strolls off. But the real work starts when the sample gets to the lab. Because fecal DNA is degraded and in low quantity, intense effort and verification is required to get reliable genotypes from fecal DNA [139, 141].

Through genetic analysis, we have found that our observations of consortship success in males were very good predictors of actual paternity - males that consorted more really did leave more offspring [128]. We also found that, while maternal sisters and brothers are very good at avoiding each other as mates [124], paternal siblings make a few more mistakes [3]. Finally, we found that paternal sisters, females that share the same father but not the same mother, seek each other out and form close relationships in the same manner that maternal sisters do [140].

Currently, we're expanding our genetic analysis to allow us to ask more detailed questions. When social groups fission permanently, so that one large group splits into two smaller ones, how do patterns of relatedness change - do females choose to go with the group in which they have more relatives? Does it matter what kind of relative it is - sisters versus mothers, aunts versus nieces, paternal versus maternal kin? [140]. When males aid juveniles during social conflicts, how often do they manage to aid their own kids rather than those fathered by another male? Do they just help any kid who might be theirs (conceived while they were actively consorting in the group)? Or do they successfully discriminate the kids that actually belong to them?

Our list of questions about genetics and relatedness if much longer than our list of answers, but we're tackling them one by one and slowly a richer and more complex picture of baboon life is emerging as a result.