Adaptive value of social learning in pinyon jays.  Learned behaviors are metabolically more expensive solutions to ecological challenges than instinctive behaviors.  Therefore, strong selective pressures favoring social learning must have existed for this trait to have evolved and be maintained in the species.  In order for social learning skills to have been shaped by natural selection, such skills have to have been variable in the population, heritable from parent to offspring, and subject to differential fitness (i.e. individuals with good social learning skills must have produced more offspring during selective events than bad social learners).  This project investigates the potential that social learning skills in pinyon jays are subject to evolution by natural selection. 

Pinyon jay home range and habitat use.  Pinyon jays are believed to rely heavily on the availability of pine seeds for overwinter survival and early reproduction.  Is the availability of pine seeds a limiting factor in the home range selection and habitat use of pinyon jays?  This project investigates the hypothesis that it is using radiotelemetry and GIS to determine what ecological factors influence the home range size and habitat use of pinyon jays.
Affects of Harness Attached Radio Transmitters on Pinyon Jays
Poster (ppt)

Unexpected population structure in pinyon jays.  Pinyon jays are typically non-irruptive, and the among-flock dispersal rate of pinyon jays is low.  Fidelity to natal flocks would imply high inbreeding and population structure.  In the metapopulation of pinyon jays in the Flagstaff area, inbreeding is high, as expected.  However, little population structure exists.  This study attempts to explain this enigma by testing three hypotheses.  First, waves of migrant jays could be disguising existing population structure.  Second, the flock might not be the breeding unit; instead, “clans” within flocks might be breeding units and therefore be responsible for expected structure.  Third, among-flock dispersal might be high enough to break down local structure.  Field observation, molecular, and mathematical techniques are being used to test these alternative possibilities.
Population Structure of a Metapopulation of Pinyon Jays (Gymnorhinus cyanocephalus)
Poster (ppt)
Poster (ppt)

Does parental investment justify genetic monogamy in pinyon jays?  Both female and male pinyon jays invest heavily in the production of offspring.  Male pinyon jays almost exclusively provision the nest during reproduction and demonstrate a higher degree of investment than most other passerines.  Variability in male investment in other species is often related to variability in the genetic monogamy of females.  Pinyon jays are socially monogamous, but are they also genetically monogamous?  This study uses molecular techniques to investigate the possibility of genetic cuckoldry in a captive flock of pinyon jays. 
Are Pinyon Jays Genetically Monogamous?
Poster (ppt)

Social cognition in pinyon jays.  It has been hypothesized that the complexities of social living have been responsible for the evolution of a variety of cognitive behaviors that can generally be called “social cognition.”  Such skills include individual recognition, the use and interpretation of graded signals, division of labor, classification and hierarchical organization, and transitive inference.  This hypothesis is being tested in the laboratory in a variety of behavioral experiments.  The experiments involve comparing social cognitive skills among closely related social and non-social species.  Social species include the pinyon jay and the Mexican jay.  Non-social species include the Clark’s nutcracker and the Western scrub jay.
Linear Hierarchy Provides Context for Evolution of Social Cognition in Pinyon Jays
Poster (ppt)

Optimality in pinyon jay foraging behavior.  Optimality theory holds that behavior maximizes payoffs and minimizes consequences in all aspects of life.  Pinyon jays are both highly social and largely dependent on pinyon seeds for overwinter survival and early reproduction.  This study uses hierarchal and pair bonding data from a captive flock in order to determine if foraging behavior is optimized for social status.
Poster (ppt)

Effects of a selective event on a pinyon jay population.  Recent severe droughts in the southwestern United States caused by global warming have led to a massive reduction in pinyon pines.  In the case of the 2002-03 drought, reduced seed production by pinyon pines led to a reduction in pinyon jay numbers.  This study investigates the hypotheses that morphological traits affecting physiological capacity and/or social status and the genetic composition of pinyon jay flocks changed as a result of this drought.
Evidence of Drought-Induced Evolution in the Pinyon Jay (Gymnorhinus cyanocephalus).
Poster (ppt)

Unusually high allelic variance in pinyon jays.  Variance in allelic polymorphism at 8 microsatellite loci is unusually high in pinyon jays compared to other animal species. At least three hypotheses explain this phenomenon. The first hypothesis suggests that there is difference in mutation rates among loci. The second hypothesis suggests that the time that each locus began to mutate was different, and older loci had more opportunity to accumulate diversity than did younger loci. The third hypothesis suggests that microsatellites linked to conserved genes are limited in their potential to diversify. Testing these three hypotheses requires knowledge of the rate of mutation at each locus. Therefore, the goals of this investigation are to determine if mutations are occurring and, if so, at what rate.
Unusually High Variance at Pinyon Jay Microsatellite Loci