Young Professional Awards

Post-doctoral Travel Award Recipients

Raoul Boughton (Archbold Biological Station)
Matt Carling (Cornell U.)
Sharon Coe (U. Arizona/USFS)
Liliana D’Alba (U. Akron)
Mark Drever (U. British Columbia)
Frank Hailer (Smithsonian Institution)
James Rivers (Oregon State U.)

Cooper Ornithological Society
Young Professional Award Finalists

The following three finalists will deliver 25-minute presentations at the YPA Plenary session on Thursday, 11 February:

Daniel C. Barton, University of Montana

“Ecological Causes of Life History Variation Tested by a Comparative-experimental Approach”

Abstract: Three alternative hypotheses (food limitation, nest predation, adult mortality) are thought to explain latitudinal variation in reproductive strategies. We tested these alternatives by comparing responses of parental provisioning rate to natural and experimental variation in brood size among species. The reaction norm of provisioning to brood size is key because it integrates critical tradeoffs, and because alternative hypotheses predict alternative patterns of variation. We found variation among 29 bird species in the slope of reaction norms of per-offspring provisioning to natural variation in brood size was explained by variation in adult mortality. Yet, species with high adult mortality appeared to adjust offspring number to parental provisioning, consistent with food limitation. We experimentally reduced broods by half in seven bird species with divergent life histories and found reduced broods showed increased per-nestling provisioning and growth, also consistent with food limitation. However, magnitudes of manipulation effect increased with adult mortality, suggesting species with low mortality reduce effort with reduced broods. These results suggest ecological factors thought to cause life history variation may interact and shift in importance across species and regions.

Andrea Townsend, Cornell University

“Suboptimal Reproductive Sharing in Cooperative Crows? An Inbreeding Extension to the Tug-Of-War Model of Reproductive Skew”

Abstract: Theory predicting how reproduction should be partitioned among family members in cooperatively breeding birds is scant, despite the vast reproductive skew literature, because the costs and benefits of inbreeding have yet to be incorporated into current skew models. Here, we extend the tug-of-war model of reproductive skew with inbreeding parameters, and test the predictions of this model in a cooperatively breeding American crow (Corvus brachyrhynchos) population. Approximately 20% of offspring in this crow population were produced through incestuous or highly inbred matings, and inbred offspring suffered severe survival costs. Using empirically derived genetic relatedness coefficients, male competitive asymmetries and a range of offspring survival probabilities, we generated expected reproductive shares of the male breeders and auxiliaries, and compared these expectations to patterns observed in the field. We found that expected values predicted observed values, but only when we specified the minimal predicted survival costs of inbreeding—the upper bound of the 95% confidence interval of the survival probability for inbred birds. Our results suggest that these crows partitioned reproduction suboptimally, given the high costs of inbreeding in this population.

Zachary Cheviron, University of California, Los Angeles

“Genetics of High-Altitude Adaptation in Rufous-Collared Sparrows (Zonotrichia Capensis)”

Abstract: Here we combine population genetic data with protein modeling analyses to test for adaptive divergence in the gene that encodes the α-subunit of the major adult hemoglobin isoform (αA-hemoglobin) in Zonotrichia capensis, a species with an exceptionally broad altitudinal distribution. We sampled 168 individuals from 17 sampling localities that are distributed along three elevational test transects and four latitudinal control transects on the west slope of the Peruvian Andes. We sequenced the entire αAhemoglobin gene in all of the sampled individuals. Each individual was also genotyped at four nuclear introns and four nuclear autosomal microsatellites. Two amino acid replacements within exon 2 of the αA-hemoglobin gene segregate within populations, and the frequency of these replacements is strongly associated with altitude. αA-hemoglobin gene flow estimates along the control transects were 70 times greater than those estimated along the elevational transects. Gene flow was not similarly reduced for the other nuclear loci. The severe reduction of altitudinal gene flow in the absence of similar reductions for putatively neutral loci is consistent with local adaptation of αA-hemoglobin to different altitudinal environments.