evolution of resource polymorphisms

Research Project | 2016

Evolution of Resource Polymorphisms

Africa (Cameroon)

The black-bellied seedcracker (Pyrenestes ostrinus) is unusual among birds in exhibiting a non-sex-related polymorphism in bill size and represents one of the few examples of disruptive selection in natural populations. Research on this species focuses on understanding the ecological and evolutionary mechanisms maintaining trophic polymorphisms in birds. This work has included measuring natural selection in natural populations, examining the genetic basis of traits through breeding experiments, and investigating ecological aspects of diet, feeding behavior and competition. Despite increasing evidence of the widespread occurrence of resource polymorphisms in vertebrates, little is known about their genetic basis.

Understanding the genetic basis of a polymorphism when the ecological basis is well understood, as in seedcrackers, has the potential of lending important insights into the evolution of discrete variation and the genetic basis of adaptation. We are currently using molecular genetic approaches to examine the population structure and phylogenetic histories of bill morphs in order to understand how disruptive selection may lead to speciation and we are exploring which genes are involved in generating bill variation.

evolution of resource polymorphismsevolution of resource polymorphisms

Related Publications

A role for migration-linked genes in genomic islands in divergence of a songbird

Ruegg, K. C.; Anderson, E. C.; Boone, J.; Pouls, J.; Smith, T. B.

Published Work | 2014 | Molecular Ecology 23(19), 4757–4769

Economic conditions predict prevalence of West Nile virus

Harrigan, R. J.; Thomassen, H. A.; Buermann, W.; Cummings, R. F.; Kahn, M. E.; Smith, T. B.

Published Work | 2010 | PLoS ONE 5(11)

Development of beak polymorphism in the African seedcracker, Pyrenestes ostrinus

Clabaut, C.; Herrel, A.; Sanger, T.; Smith, T. B.; Calsbeek, A.

Published Work | 2009 | Evolution and Development 11(6), 636–646

Isolation of polymorphic tetranucleotide microsatellite markers for the black-bellied seedcracker (Pyresnestes ostrinus)

Delaney, K. S.; Pires, D.; Holder, K.; Bardeleben, C.; Smith, T. B.

Published Work | 2005 | Molecular Ecology Notes 5(4), 774–776

Refugial isolation vs. ecological gradients: Testing alternative mechanisms of evolutionary divergence in four rainforest vertebrates

Smith, T. B.; Schneider, C. J.; Holder, K.

Published Work | 2001 | Genetica 112, 383–398

Does bill size polymorphism affect courtship song characteristics in the African finch Pyrenestes ostrinus?

Slabbekoorn, H.; Smith, T.

Published Work | Biological Journal of the Linnean Society 71(4), 737–753

Reaching new adaptive peaks: Evolution of bill size polymorphism in an African finch

Smith, T. B.; Girman, D.

Published Work | 2000 | Adaptive Genetic Variation in the Wild

A novel pattern of reversed sexual dimorphism in fairy-wrens: implications for sexual selection

Swaddle, J. P.; Karubian, J.; Pruett-Jones, S.

Published Work | 2000 | Behavioral Ecology 11(3), 345–349

A role for ecotones in generating rainforest biodiversity

Smith, T. B.; Wayne, R. K.; Girman, D.; Bruford, M. W.

Published Work | 1997 | Science 276(5320), 1855–1857

The ecology of resource polymorphisms in vertebrates: a reply

Skúlason, S.; Smith, T. B.

Published Work | 1996 | Trends in Ecology and Evolution 11(1), 26

Evolutionary significance of resource polymorphisms in fish, amphibians and birds

Smith, T. B.; Skúlason, S.

Published Work | 1996 | Annual Review of Ecology and Systematics 27, 111–133

Resource polymorphisms in vertebrates

Skulason, S.; Smith, T.B.

Published Work | 1995 | Trends in Ecology & Evolution 10(9), 366-370

The preservation of process: the missing element of conservation programs

Smith, T. B.; Bruford, M. W.; Wayne, R. K.

Published Work | 1993 | Biodiversity Letters 1(6), 164–167

Ecological and evolutionary significance of a third bill form in the polymorphic finch Pyrenestes ostrinus

Smith, T. B.

Published Work | 1993 | Birds and the African Environment: Proceedings of the Eighth Pan-African Ornithological Congress 268

A double-billed dilemma

Smith, T.B.

Published Work | 1991 | Natural History 100(1), 14-21

Patterns of morphological and geographic variation in trophic bill morphs of the African finch Pyrenestes

Smith, T. B.

Published Work | 1990 | Biological Journal of the Linnean Society 41(4), 381–414

Resource use by bill morphs of an African finch: Evidence for intraspecific competition

Smith, T. B.

Published Work | 1990 | Ecology 71(4), 1246–1257

Portable device for measuring seed-hardness

Smith, R. J.; Smith, T. B.

Published Work | 1989 | Journal of Field Ornithology 60(1), 56–59

Blood parasites of birds in Cameroon

Kirkpatrick, C.E.; Smith, T.B.

Published Work | 1988 | The Journal of Parasitology 74(6), 1009-1013

Bill size polymorphism and interspecific niche utilization in an African finch

Smith, T. B.

Published Work | 1987 | Nature 329, 717-719

Cracking the problem of bill size

Smith, T. B.; Smith, P. B.

Published Work | 1987 | Riverbanks 5, 2–8